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Aggregates - 2017 (75)

PROFICIENCY TESTING

PROGRAM REPORT

Accredited for compliance with ISO/IEC 17043

Copyright: LabSmart Services Pty Ltd

Aggregates Proficiency Testing Program - 2017(75)

Copyright: LabSmart Services Pty Ltd Issued - March 2018 of 68

Program Report This report is available on the LabSmart Services website. The issue of this proficiency report was authorised by Peter Young, Director, LabSmart Services Pty Ltd, March 2018. Contact Details

Email: [email protected] Mobile: 0432 767 706 Fax: (03) 8888 4987

Program Coordinator The program coordinator for this program was Peter Young, Director, LabSmart Services Pty Ltd. Contact Details

Email: [email protected] Mobile: 0432 767 706 Fax: (03) 8888 4987

Please note that any technical questions regarding this program are to be directed to the program coordinator.

Z-scores Summary A z-scores summary for this program was issued in December 2017. This technical program report supersedes the z-sores summary.

Accredited Proficiency Testing Provider LabSmart Services is accredited by NATA to ISO/IEC 17043, Conformity assessment – General requirements for proficiency testing. Accreditation number 19235. The accreditation provides additional assurance to participants of the quality and importance we place on our proficiency testing programs.

LabSmart Services More details regarding our proficiency testing services can be found on our website.

www.labsmartservices.com.au

Copyright This work is copyright. No part of this publication may be reproduced in any form, transmitted or stored in any repository (e.g. mechanical, digital, electronic or photographic) without prior written permission of LabSmart Services Pty Ltd. Please contact LabSmart Services should you wish to reproduce any part of this report.

Amendment History Reports may be downloaded from the LabSmart Services website.

Version 1 – Issued 31 March 2018



CONTENTS PAGE

1. Program Aim

4

2. Performance

2.1 Identified Outliers 2.2 Overall Performance

4

4 5

3. Technical Comments

3.1 Particle Size Distribution 3.2 Material Finer Than 75 um 3.3 Particle Shape Proportional Calliper 3.4 Flakiness Index 3.5 Average Least Dimensions 3.6 Particle Density 3.7 Water Absorption 3.8 Summary of test results (unrounded)

7

7 17 17 19 20 23 25 26

4. Statistics: Z- Scores & Graph

4.1 PSD (% Passing) – 13.2 mm PSD (% Passing) – 9.5 mm PSD (% Passing) – 6.7 mm PSD (% Passing) – 4.75 mm 4.2 Material finer than 75 µm 4.3 Particle shape by proportional calliper (2:1) 4.4 Particle shape by proportional calliper (3:1) 4.5 Flakiness index 4.6 Average least dimensions 4.7 Apparent particle density 4.8 Particle density on a dry basis 4.9 Particle density on a saturated – surface dry basis 4.10 Water absorption

28

28 30 32 34

36

38

40

42

44

46

48

50

52

5. Program Information

5.1 Z-score Summary 5.2 Program Design 5.3 Sample Preparation 5.4 Packaging and Instructions 5.5 Quarantine 5.6 Sample Dispatch 5.7 Homogeneity Testing 5.8 Participation 5.9 Statistics 5.10 Non-statistical Outliers

54

54 54 57 57 57 57 57 58 58 61

Appendix A Instructions for testers

Appendix B Results log

Appendix C Calculated ‘% Retained’

62

64

66



1. Program Aim The proficiency program was conducted in October\November 2017 with 99 participants throughout Australia. The program involved the performance of the following ten tests.

▪ AS 1141 11 Particle size distribution ▪ AS 1141 12 Material finer than 75 µm ▪ AS 1141 14 Particle shape by proportional calliper (2:1) ▪ AS 1141 14 Particle shape by proportional calliper (3:1) ▪ AS 1141 15 Flakiness index ▪ AS 1141 20.1 Average least dimensions ▪ AS 1141 6.1 Apparent particle density ▪ AS 1141 6.1 Particle density on a dry basis ▪ AS 1141 6.1 Particle density on a saturated–surface dry basis ▪ AS 1141 6.1 Water absorption

Testing to the relevant sections of AS 1141 was preferred but other equivalent methods were accepted. The program provides confidence to the construction materials testing industry regarding the competency of participants (and the industry) to perform these tests. Each participant’s performance is statistically assessed and used as a measure of competency relative to all those who participated. Other measures of performance are also used. This report has been prepared using robust statistics. Information regarding the conduct and design of the program can be found in section 5. Comprehensive technical comment (section 3) is provided to assist participants improve the overall performance of these tests. In addition, test data has been reviewed for consistency and additional feedback regarding aspects of the test are provided.

2. Performance 2.1 Identified Outliers There were 51 outliers identified across the ten tests performed. These were spread across 30 participants. This represented 33% of the 92 participants who returned results in the proficiency program (Table 2.1). Participant’s test results are tabulated in section 4 along with the robust statistics and a z-score graph. The z-score indicates how far away a participant is from the program’s median value. A z-score of zero indicates a strong consensus with respect to all other participants and represents a very good outcome. The z-score graph gives a quick visual indication of how a result compares to others in the program. Outliers are where a z-score value is greater than 3 or less than -3. It is recommended that participants with outliers investigate their performance of the test. Participants with outliers are detailed in table 2.1.



Those participants with z-scores greater than 2 or less than -2 may wish to review their testing methodology. Only those approaching a z-score of 3 (i.e. outside ± 2.75) have been specifically identified in table 2.1A as feedback. More detail on the robust statistics used can be found in section 5. Technical comment and feedback in section 3 is provided to assist participants investigate or review their results as well for those seeking to improve their testing performance.

Test Investigate Review

Particle size distribution (% Passing) 13.2 mm B6 A2, R5

9.5 mm - (G7), T4

6.7 mm K6, T4, Y6, Q5, X7, F8, E4, L7, Y5

4.75 mm L6, N9, C2, K6, D7, T4, Z3, Y6, Q5, F8, E4, L7,

X7, -

Material finer than 75 µm (by washing) Z3, Y6, D4, Q5, E4, L7 Y3

Particle shape by proportional calliper (2:1) A2, S6 (P5), (L4)

Particle shape by proportional calliper (3:1) P5, S6 T2, Q3

Flakiness index - -

Average least dimensions X6, W7 L7, (N9)

Apparent particle density T4, L9, Y5, J8, E9, L4 -

Particle density on a dry basis G3, T4, J8, E9, L4 (F4), (Q2)

Particle density on a saturated-surface dry basis F4, G3, T4, J8, E9, L4 (Q2), (P7), (K5), (J9)

Water absorption L9, Y5, Q2 -

Table 2.1A Participant codes where further action is recommended based on z-scores. Those codes shown in brackets are very close to 2.75.

2.2 Overall Performance Overall a satisfactory level of performance(1) was achieved by the majority (67%) of participants with 33% having one or more outliers(2). The performance by participants is very good overall and compares favourably with previous aggregate proficiency programs. There were 99 participants registered for the program with 92 participants(2) (93%) returning results.



There were more outliers in this program than in either the 2015(60) or 2016(68) proficiency programs. It indicates that there is considerable room for improvement. Section 3 provides comments on possible ways to improve. Outliers are not the only indicator of satisfactory performance in a proficiency program. It should be noted that this report identifies inaccurate and incorrect calculations in several instances. These are just as unacceptable as outliers. In the many instances these matters could have been picked up with better laboratory practices, in particular, through the use of check sums and general checking by a supervisor. The proficiency program was a useful exercise, allowing laboratories to have greater confidence in their results while for others providing an opportunity to improve their competency with respect to the tests in this program. The following is a summary of the test results obtained (Table 2.2A). Unrounded statistics for the program are shown in section 3.8.

Test Units Participants Median Normalised

IQR

Particle size distribution (% Passing) 13.2 mm

% 92

62 1.0

9.5 mm 40 1.1

6.7 mm 10 0.7

4.75 mm 4.6 0.4

Material finer than 75 µm (by washing) % 84 2.8 0.3

Particle shape by proportional calliper (2:1) % 44 14.7 5.9


Flakiness index % 63 8.4 1.5

Average least dimensions mm 54 7.9 1.1

Apparent particle density t/m3 48 2.81 0.02

Particle density on a dry basis t/m3 48 2.64 0.02

Particle density on a saturated-surface dry basis t/m3 47 2.70 0.02

Water absorption % 48 2.4 0.3

Table 2.2A Summary of rounded test results from the program.

(1) Overall performance outcomes can vary from one aggregate program to another and should not

be taken as either an improvement or deterioration in industry performance. Variation in program outcomes may be attributed to the difficulty of the material under test or where participants overall in one program may have more experience or greater skill levels than those in another program. Evaluation of industry performance endeavours to balance these issues. Industry outcomes and individual performance outcomes are detailed in section sections 2.2 and 3.

(2) Statistics relating to the number of outliers or participation rates are intended as an overview only for the aggregates program. They are calculated based on the total number of participants, however not all participants perform each test.



3 Technical Comments The more often a participant’s code appears during the following feedback the greater the need to investigate testing practice in general. A participant code shown in bold indicates an outlier or is associated with an outlier. Participants are reminded that they can update their results up until the z-score summary is issued. Many participants or supervisors on reflecting on the results forwarded realize that there is an error. These changes can be accepted. Changes to results after the z-scores have been published however cannot be accommodated. Note: Some participants did not indicate that they had used the nominated test method shown on the log sheet. This report has assumed that the nominated test method has been used.

‘% Retained’ – Appendix C

Mass retained results are often helpful in understanding issues associated with testing. Therefore, ‘% Retained’ and associated z-scores have been calculated for information purposes only and are shown in Appendix C. Participants do not have to investigate the z-scores greater than 3 in Appendix C. In many cases if the ‘retained mass’ was incorrect to begin with then it will result in a z-score greater than 3. For the retained results to correlate with the ‘% Passing’ then the majority of participants need to supply “% retained” results or retained masses. Six did not supply sufficient information (shown in orange) in Appendix C to allow calculation of “% mass retained”. Rows shown in green correspond to “% Passing” PSD outliers and identified as possibly having a high z-score for other fractions. Rows in yellow show “% mass retained” results where the z-score was greater than three and corresponds to a ‘% passing’ z-score around 2.75. It may indicate an issue with the mass data submitted or inaccurate calculations. The “% mass retained” data detailed in Appendix C may be reference throughout section 3 of this report. 3.1 Particle Size Distribution General

The performance of the sieve analysis by participants was good with the variation (s.d) at around 1% or less for most fractions. Many of the comments also refer to ‘Material finer than 75 µm’ as well. There were 92 participants in the PSD test. There were 22 participants that had some material retained on the 19.0mm sieve. See table 3.1C. Z-scores have not been calculated due to both the low number of participants involved and the small amount retained on this fraction. The amounts are small and have minimal impact on the analysis and z-score calculated for the remaining fractions. Participants with material on the 19.0mm sieve should check that sieving had been thoroughly carried out.



With the PSD test ‘errors’ can flow though multiple fractions leading to multiple outliers as shown in table 3.1A. Fifteen participants (16%) were identified with one or more outliers for the PSD test. In total, there were 25 outliers. It is recommended that these participants investigate the results obtained.

Particle Size Distribution (% Passing)

CODE 13.2 mm

9.5 mm

6.7 mm

4.75 mm

<75 um

B6

A2

R5

G7

T4

K6

Y6

Q5

X7

L6

N9

C2

D7

F8

E4

L7

Y5

Z3

D4

Y3

Table 3.1A PSD outliers (green) and near outliers (yellow) combined.

Most participants with outliers appeared to have satisfactory “% mass retained” results (Appendix C). This would suggest the issue may involve the calculation of “% Passing” rather than any issue with the raw data. There are eight participants (A2, R5, G7, T4, F8, E4, L7, Y5) where z-scores were close to or greater than 2.75. In these cases, it may be beneficial for these participants to review their results. There are 4 participants (T4, Z3 Y6, & B6) that had outliers in both the ‘% Passing’ and ‘% Retained’. This suggests that there may be an issue with sieving technique or the incorrect recording of a mass. There are 10 participants (L6, N9, C2, K6, D7, Q5, F8, E4, L7 & X7) with outliers but where the ‘% Retained’ results looked fine. This may mean the ‘% Passing’ result has been incorrectly calculated. Also look at the ‘% Retained’ results where the z-score is



increasing or decreasing over several fractions. See if this may account for the observed outlier for one or more of the ‘% Passing’ fractions. This could indicate a calculation error or incomplete/over sieving. Participant Y3 had a high result for the 4.75 fraction but had submitted no mass retained data so further comment could not be made. There were a few participants (B5, Q5, & X7) where one or more ‘% passing’ results had not been provided and the program co-ordinator had to calculate them on the participants behalf (shown in green on z-score tables). These participants need to investigate the reasons for the non-provision of results. Two Q5 and X7 had outliers identified as well. The following feedback is provided for laboratories who wish to improve their testing practices or investigate outliers. Sieve Diameter

The majority of participants used 300 mm diameter sieves. Eight participants did not indicate which sieve diameter sieve set was used. Ten (M2, L9, Y5, P3, D6, K7, G9, F8, X4 & B6) used 200 mm diameter sieves (20%). Sieve Overload

From table 3.1B those using a 200mm diameter sieve set would need to have split the sample. Even those using a 300mm diameter set were very close to the limit on the 6.7mm fraction. To handle the ‘overload’ the sample could have been sieved in two passes. This also avoids the possibility of segregation when splitting. Alternatively the sample could have been split and a portion sieved.

Sieve Typical retained mass on 300 mm diameter sieve

g

300 mm overload values

g

200 mm overload values

g

13.2 540 900 400

9.5 330 600 250

6.7 440 500 225

4.75 100 400 200

Table 3.1B ‘Sample A’ average mass per sieve and sieve overload limits.

Three of the participants (B6, F8, Y5) used 200mm diameter and had outliers suggesting something may have gone astray with the splitting/calculation process. The need to sieve in more than one pass or split complicates the calculation process and the possibility of an incorrect calculation increases. Thorough checking is important. It is recognised that this is a difficult task in ‘one person’ laboratories.



Splitting

The program supplied a 1.5 kg of ‘Sample A’ for PSD with all participants using this amount for the test. All but six participants (U3, M8, Y3, N2, E7, K2) provided a start mass (see Appendix C - Codes in orange). Participants that use significantly different starting masses can influence a participant’s performance in relation to other participants. Therefore, the program instructions indicated to use all of ‘Sample A’ for the test. All participants indicated that the whole sample had been used. A poorly mixed sample or poor splitting technique may have a significant impact on the results. Depending on the diameter of the sieves used overloading or calculation errors may also contribute to different performance outcomes. Washing

Some participants did not supply a ‘Material finer than 75 μm’ result even through a ‘washed mass’ was supplied. A low ‘Material finer than 75 μm’ result may indicate poor washing techniques. Most appear to have washed the sample but those with very high pan amounts may not have. For further discussion see ‘Pan’ in this section and section 3.2. Drying

Six participants (A2, P8, N9, P5, U3 & K2) indicated using a ‘hot plate’ rather than an oven to dry the material. The test method does allow for this but only in cases where it can be shown not to affect the results. This generally applies to material where the history is known such as in a quarry for example. For unknown material such as in a proficiency program it is recommended that the standard oven method should be used. Approximately ten participants did not indicate the drying method used. % Passing

For each participant the ‘% Passing’ values were also recalculated from the mass retained data submitted and compared to each participant submitted ‘% Passing’ results. Most participant’s calculations were identical to the recalculated ‘% Passing’ or within an acceptable rounding tolerance (i.e. <0.5%). The value 0.5 % was chosen as the point where such a difference could affect the result reported when rounded. It should be noted that such errors can be cumulative and if occur on larger aperture sieves it can flow through to the smaller aperture sieves. Participant’s results where one or more ‘% Passing’ results were greater than 0.5 % are shown in table 3.1C in yellow highlight. In many cases they were significantly ‘out’ and showed as outliers. There were around 15% identified as having an incorrect ‘% Passing’ result based on what was submitted. This is the same percentage as the last program. Those shown in bold also had outliers identified for PSD.



I.e. D5, L6, N9, S2, C2, E3, K6, T4, Z3, C5, F8, G6, L7 & X7 Participants with codes highlighted in blue (8%) failed to supply some aspect of the raw data requested and the results could not be recalculated. (see ‘Incomplete or inaccurate results’).

There is a possibility that, due to the number and magnitude of the errors incurred, that they could cause a shift in the z-scores statistics. Check Sums

Particle size distribution calculations should have “check sums” as an aid to detecting errors. Several approaches can be used for ‘hand calculated’ results. For computer spreadsheets a single check sum that adds all the weights and compares it to the starting mass is usually sufficient. If a check sum does not agree it may mean that there has been an incorrect reading of the balance, transcription error, incorrect calculation or possibly lost material. The sign associated with the difference gives a clue as to where to begin. Participant’s masses were added and checked against the start mass. A number of participants did not supply the mass retained results, so checks could not be performed (see table 3.1C – codes shown in blue). It is desirable that any ‘unaccounted mass’ be less than 1%. The majority of participants ‘unaccounted mass’ was very low, less than 0.5 %. This is a very good outcome. Participants L6, K9, S2, E3, V8, J2, Z3, C5, E6, P3, D6, K9, G9, G6, P7 & K5 check mass unaccounted values were higher than 1%. These participants may benefit from reviewing the data and calculations submitted. There were a few participants (K9, V8, J2, G6) where the “check sums” yielded abnormal numbers suggesting that some aspect of the data submitted was incorrect. Pan

Assessment of the pan contents depends largely on the knowledge of the material as to what is acceptable. The material used for this program broke down a little during sieving. Pan amounts around 30g could be expected i.e. about 2% retained. Most participants had pan amounts around 2% retained. Overall the breakdown in material had minor influence on the ‘% passing’ results obtained. The following participants were significantly outside the expected range based on other participants pan results. K9, D7, V8, J2, C5, E6, P3, G6, P7 and K5 Those participants with low pan amounts may have lost material during sieving or washing, not sieved long enough or there has been a calculation/transcription error.



Participants with high pan amounts may have over sieved, not washed completely or there has been a calculation/transcription error. Some participants may have sieved without washing. Pan amounts are important in the checking process. Although in this program they do not constitute an outlier they can affect the ‘material finer than 75 µm’ result. Four participants (U3, R4, D4 & E7) did not submit values for material retained in the pan. It is good practice to record this amount and use it in the “Checksum” process. Several participants did not submit results for “material finer than 75um” but from the pan amounts it was apparent that the aggregate had been washed. Even if a participant does not perform the “material finer than 75um” test participants still need to wash the sample. Retained dust on the aggregate may affect the ‘% passing Results” by 1 or 2% on various fractions. Incomplete or inaccurate results

Many participants only supplied some of the data requested. For example often the following was missing:

• Initial dry mass

• Washed mass

• Both washed and dry mass

• Mass retained

• All of above Participants with incomplete data (8%) are shown in table 3.1C with codes shaded blue. Incomplete data means only limited feedback can be given. There were seven participants (U3, M8, Y3, J8, N2, E7 & K2) with incomplete data. Based on the data supplied there were several possibly incorrect calculations identified in table 3.1C. Participants with significant differences are highlighted in yellow “N” in the table. Some participants dropped trialling zeros i.e. 64 instead of 64.0. This is poor practice. It is unknown to the person checking if indeed the zero has been left off or a figure not recorded. The result may have been incorrectly rounded. The result shown as 64 may have been 64.0, 64.3, 64.9 or 63.8 etc.



19.0 mm 13.2 mm 9.5 mm 6.7 mm 4.75 mm

Code %

Passing Recalculated % Passing

Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 %

0.5 0.5 0.5 0.5 0.5

P4 100 62.6 62.6 0.0 Y 40.0 40.0 0.0 Y 10.4 10.4 0.0 Y 4.7 4.7 0.0 Y

A2 100 65 64.8 0.2 Y 42 42.2 -0.2 Y 11 10.8 0.2 Y 5 4.8 0.2 Y

D5 100 63 62.6 0.4 Y 40 39.9 0.1 Y 11 10.2 0.8 N 5 4.6 0.4 Y

L6 100 99.3 0.7 N 62 62.1 -0.1 Y 41 40.7 0.3 Y 11 11.1 -0.1 Y 6 5.5 0.5 N

K9 100 62.0 62.5 -0.5 Y 40.0 40.1 -0.1 Y 9.3 9.3 0.0 Y 4.2 4.2 0.0 Y

M5 100 60.9 60.9 0.0 Y 39.6 39.6 0.0 Y 10.9 10.9 0.0 Y 5.1 5.1 0.0 Y

P8 100 63 62.7 0.3 Y 41 40.6 0.4 Y 10 10.2 -0.2 Y 5 4.7 0.3 Y

C3

N9 100 62.2 63.4 -1.2 N 37.7 39.7 -2.0 N 8.5 11.5 -3.0 N 2.2 5.4 -3.2 N

T2 100 62.3 62.3 0.0 Y 41.1 41.1 0.0 Y 10.7 10.7 0.0 Y 4.8 4.8 0.0 Y

X6 100 62.7 62.7 0.0 Y 40.6 40.6 0.0 Y 10.3 10.3 0.0 Y 4.6 4.6 0.0 Y

G7 100 63.8 63.8 0.0 Y 42.9 42.9 0.0 Y 10.3 10.3 0.0 Y 4.5 4.5 0.0 Y

A4

Q3 100 62.7 62.7 0.0 Y 40.4 40.4 0.0 Y 9.9 9.9 0.0 Y 4.6 4.6 0.0 Y

R5 100 65 64.9 0.1 Y 41 40.7 0.3 Y 11 10.7 0.3 Y 5 4.8 0.2 Y

W6 100 62.5 62.5 0.0 Y 40.1 40.1 0.0 Y 9.9 9.9 0.0 Y 5.0 5.0 0.0 Y

S2 100 62.7 62.7 0.0 Y 40.2 46.9 -6.7 N 10.7 17.4 -6.7 N 4.8 11.6 -6.8 N

B9 100 61.6 61.6 0.0 Y 39.2 39.2 0.0 Y 10.3 10.3 0.0 Y 4.6 4.6 0.0 Y

U3 100 60.1 38.6 9.5 4.5

P5 99.2 99.2 0.0 Y 62.1 62.1 0.0 Y 40.1 40.1 0.0 Y 10.0 10.0 0.0 Y 5.0 5.0 0.0 Y

G8 100 62.6 62.6 0.0 Y 40.3 40.3 0.0 Y 10.0 10.0 0.0 Y 4.6 4.6 0.0 Y

C2 100 61.6 62.8 -1.2 N 40.2 42.1 -1.9 N 8.5 11.4 -2.9 N 1.9 5.0 -3.1 N

F4 100 64.6 64.6 0.0 Y 41.6 41.7 -0.1 Y 11.5 11.5 0.0 Y 5.3 5.3 0.0 Y

M8 95.4 60.3 38.1 9.6 3.6

E3 99.3 99.3 0.0 Y 62.9 76.2 -13.3 N 39.3 52.6 -13.3 N 9.9 23.2 -13.3 N 4.9 18.2 -13.3 N

R4 100 63.2 63.2 0.0 Y 40.1 40.1 0.0 Y 10.1 10.1 0.0 Y 4.5 4.5 0.0 Y

N8 100.0 61.3 61.3 0.0 Y 39.8 39.8 0.0 Y 10.6 10.6 0.0 Y 4.7 4.7 0.0 Y

Table 3.1 C Variation in results compared to those calculated based on data submitted



Code

19.0 mm 13.2 mm 9.5 mm 6.7 mm 4.75 mm

% Passing

Recalculated % Passing

Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 %

0.5 0.5 0.5 0.5 0.5

M2 100 61.6 61.6 0.0 Y 38.6 38.6 0.0 Y 9.8 9.8 0.0 Y 4.4 4.4 0.0 Y

B8 100 60.4 60.4 0.0 Y 40.5 40.5 0.0 Y 10.1 10.1 0.0 Y 4.2 4.2 0.0 Y

J5 98.0 98.0 0.0 Y 61.8 61.8 0.0 Y 39.7 39.7 0.0 Y 9.4 9.4 0.0 Y 4.6 4.6 0.0 Y

K6 100 64.0 62.9 1.1 N 41.6 39.8 1.8 N 13.1 10.3 2.8 N 7.9 5.0 2.9 N

F5 100.0 62.3 62.3 0.0 Y 40.0 40.0 0.0 Y 9.4 9.4 0.0 Y 4.2 4.2 0.0 Y

Q4 98.7 98.7 0.0 Y 62.3 62.3 0.0 Y 41.1 41.1 0.0 Y 10.6 10.6 0.0 Y 5.2 5.2 0.0 Y

R9 100.0 61.25 61.2 0.0 Y 39.78 39.8 0.0 Y 10.2 10.2 0.0 Y 4.46 4.5 0.0 Y

Y4 97.3 97.3 0.0 Y 62.3 62.3 0.0 Y 40.5 40.5 0.0 Y 11.1 11.1 0.0 Y 5.2 5.1 0.1 Y

G3 98.0 98.0 0.0 Y 62.5 62.5 0.0 Y 39.6 39.6 0.0 Y 10.1 10.1 0.0 Y 4.4 4.5 -0.1 Y

W8 100 61.7 61.7 0.0 Y 38.4 38.4 0.0 Y 10.1 10.1 0.0 Y 5.0 5.0 0.0 Y

X2 100 62.5 62.5 0.0 Y 37.8 37.8 0.0 Y 10.7 10.6 0.1 Y 5.1 5.1 0.0 Y

L8 99.3 99.3 0.0 Y 63.2 63.2 0.0 Y 40.6 40.6 0.0 Y 11.0 11.0 0.0 Y 5.1 5.1 0.0 Y

D7 99.4 99.4 0.0 Y 61.7 61.7 0.0 Y 40.7 40.7 0.0 Y 11.8 11.8 0.0 Y 7.2 7.2 0.0 Y

B5 100 63.8 63.8 0.0 Y 39.9 39.9 0.0 Y 10.5 10.5 0.0 Y 4.5 4.5 0.0 Y

V8 100 62.1 62.1 0.0 Y 39.6 39.6 0.0 Y 9.7 9.7 0.0 Y 4.4 4.4 0.0 Y

J2 100 64.25 64.2 0.0 Y 39.16 39.2 0.0 Y 9.80 9.8 0.0 Y 3.98 4.0 0.0 Y

Y3 100 63.0 40.2 10.6 5.1

N7 100 62.7 62.7 0.0 Y 39.6 39.6 0.0 Y 10.5 10.5 0.0 Y 4.6 4.5 0.1 Y

T4 99.4 99.4 0.0 Y 60.1 61.7 -1.6 N 36.8 39.4 -2.6 N 0.7 4.8 -4.1 N 0.6 4.7 -4.1 N

Z3 98 98.5 -0.5 N 62 62.5 -0.5 Y 38 39.5 -1.5 N 8.5 10.3 -1.8 N 2.7 -46.6 49.3 N

Q7 100 62 62.0 0.0 Y 41 41.3 -0.3 Y 11 10.6 0.4 Y 5 4.7 0.3 Y

Y6 100 61 61.0 0.0 Y 38 38.1 -0.1 Y 8.0 8.2 -0.2 Y 2.5 2.8 -0.3 Y

C5 100 62 76.1 -14.1 N 40 54.0 -14.0 N 9 23.6 -14.6 N 5 -21.4 26.4 N

V9 100 62.8 62.8 0.0 Y 40.5 40.5 0.0 Y 10.4 10.5 -0.1 Y 4.7 4.7 0.0 Y

D4 100 62 61.9 0.1 Y 39 39.0 0.0 Y 9.0 9.5 -0.5 Y 5.0 4.8 0.2 Y

Q5 98.7 98.7 0.0 Y 61.4 61.4 0.0 Y 37.7 37.6 0.1 Y 7.6 7.5 0.1 Y 2.6 2.4 0.2 Y

L9 99 99.4 -0.4 Y 62 62.2 -0.2 Y 40 39.9 0.1 Y 11 11.0 0.0 Y 4 4.5 -0.5 Y




Code

19.0 mm 13.2 mm 9.5 mm 6.7 mm 4.75 mm

% Passing


Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 %

0.5 0.5 0.5 0.5 0.5

Y5 99 99.3 -0.3 Y 62 62.2 -0.2 Y 40 39.7 0.3 Y 12 11.5 0.5 Y 5 4.5 0.5 Y

J7 100 62.5 62.5 0.0 Y 40.0 39.9 0.1 Y 9.4 9.4 0.0 Y 4.2 4.2 0.0 Y

A8 100 62.9 62.9 0.0 Y 39.2 39.2 0.0 Y 10.1 10.1 0.0 Y 4.9 4.9 0.0 Y

E6 97 97.5 -0.5 Y 61 61.4 -0.4 Y 39 39.1 -0.1 Y 11 10.5 0.5 Y 5 4.7 0.3 Y

X8 100 63 62.8 0.2 Y 41 41.1 -0.1 Y 11 11.2 -0.2 Y 5 5.4 -0.4 Y

U9 100 63.1 63.1 0.0 Y 41.5 41.5 0.0 Y 11.5 11.5 0.0 Y 5.1 5.1 0.0 Y

J8 99.7 62.8 40.6 10.7 5.2

L3

A9

S8 100.0 63.2 63.2 0.0 Y 40.7 40.7 0.0 Y 11.1 11.1 0.0 Y 4.9 4.9 0.0 Y

P3 99.3 99.3 0.0 Y 62.1 62.1 0.0 Y 40.2 40.2 0.0 Y 10.9 10.9 0.0 Y 5.1 5.1 0.0 Y

D6 100 63.3 63.3 0.0 Y 39.1 39.1 0.0 Y 11.1 11.1 0.0 Y 5 5.0 0.0 Y

K7 100 62.2 62.2 0.0 Y 40.6 40.6 0.0 Y 11 11.0 0.0 Y 5.2 5.1 0.1 Y

G9 100 62.9 62.9 0.0 Y 41.3 41.3 0.0 Y 11.2 11.2 0.0 Y 5.4 5.4 0.0 Y

F8 99.4 99.4 0.0 Y 62.3 63.4 -1.1 N 39.0 40.7 -1.7 N 8.2 10.8 -2.6 N 2.4 5.1 -2.7 N

Q2 100 63.3 63.3 0.0 Y 40.6 40.6 0.0 Y 10.4 10.4 0.0 Y 4.5 4.5 0.0 Y

E5 100 62.8 62.8 0.0 Y 40.6 40.6 0.0 Y 10.2 10.2 0.0 Y 4.8 4.8 0.0 Y

B7 100 63.3 63.3 0.0 Y 40.2 40.2 0.0 Y 10.6 10.6 0.0 Y 4.9 4.9 0.0 Y

N2 100 63.7 40.3 10.2 4.6

W7 100 61.7 61.7 0.0 Y 39.0 39.0 0.0 Y 9.9 9.9 0.0 Y 4.6 4.6 0.0 Y

Y8 100 61.7 61.7 0.0 Y 39.1 39.2 -0.1 Y 10.0 10.0 0.0 Y 4.6 4.7 -0.1 Y

G6 100 63.5 97.6 -34.1 N 40.5 96.0 -55.5 N 10.3 94.0 -83.7 N 4.4 93.6 -89.2 N

T9 100 63.3 63.3 0.0 Y 41.0 41.0 0.0 Y 10.5 10.5 0.0 Y 4.6 4.6 0.0 Y

R2 98.2 98.2 0.0 Y 62.3 62.3 0.0 Y 40.4 40.4 0.0 Y 10.4 10.4 0.0 Y 4.7 4.7 0.0 Y

E4 100 61.1 61.1 0.0 Y 37.8 37.8 0.0 Y 8.1 8.1 0.0 Y 2.8 2.8 0.0 Y

L7 100 62.0 63.2 -1.2 N 39.1 41.0 -1.9 N 8.1 11.0 -2.9 N 2.4 5.4 -3.0 N

P6




Code

19.0 mm 13.2 mm 9.5 mm 6.7 mm 4.75 mm

% Passing


Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 % %


Difference

<0.5 %

0.5 0.5 0.5 0.5 0.5

K3 96.60 96.6 0.0 Y 60.40 60.4 0.0 Y 37.30 37.3 0.0 Y 9.50 9.5 0.0 Y 4.70 4.7 0.0 Y

D8

S3 100.0 62.2 62.2 0.0 Y 41.5 41.5 0.0 Y 9.8 9.8 0.0 Y 4.7 4.7 0.0 Y

M6 100 62 61.7 0.3 Y 40 40.1 -0.1 Y 10 10.0 0.0 Y 4.4 4.3 0.1 Y

P7 100 63.21 63.2 0.0 Y 39.81 39.8 0.0 Y 10.74 10.7 0.0 Y 4.34 4.3 0.0 Y

K5 100 63.82 63.8 0.0 Y 41.30 41.3 0.0 Y 10.79 10.8 0.0 Y 4.59 4.6 0.0 Y

R6 100 61.9 61.9 0.0 Y 40.8 40.8 0.0 Y 9.8 9.7 0.1 Y 4.5 4.5 0.0 Y

T8 100 60.8 60.8 0.0 Y 37.4 37.4 0.0 Y 9.0 9.0 0.0 Y 4.3 4.3 0.0 Y

X4 100 60.6 60.6 0.0 Y 38.7 38.7 0.0 Y 10.1 10.1 0.0 Y 4.8 4.8 0.0 Y

B6 100 58.9 58.9 0.0 Y 39.1 39.1 0.0 Y 9.7 9.7 0.0 Y 4.6 4.6 0.0 Y

F7 100 61.6 61.6 0.0 Y 39.6 39.6 0.0 Y 10.3 10.3 0.0 Y 4.5 4.4 0.1 Y

E9 99 99.4 -0.4 Y 62 62.4 -0.4 Y 40 40.0 0.0 Y 10 10.1 -0.1 Y 4 4.5 -0.5 Y

L4 100 61 61.0 0.0 Y 40 39.8 0.2 Y 10 10.2 -0.2 Y 5 4.9 0.1 Y

M4 100 63 62.9 0.1 Y 42 41.5 0.5 Y 10 10.1 -0.1 Y 5 4.8 0.2 Y

E7 100 62 40 10 5

S6 100 59.96 60.0 0.0 Y 39.49 39.5 0.0 Y 9.13 9.1 0.0 Y 4.48 4.5 0.0 Y

X7 99 98.6 0.4 Y 61 62.4 -1.4 N 38 40.3 -2.3 N 7 10.2 -3.2 N 2 5.3 -3.3 N

K2 100 61.9 39.5 10.1 4.6




3.2 Material finer than 75 μm Participants’ overall performed was reasonable for this test with several participants identified where improvement could be made. In addition to the z-scores calculated all calculations were checked using the supplied participant data. Several participants did not report to the number of decimal places requested (G7, R5, N7, Z3, Y6, L9, Y5, Q2, X4 & E7). This unfortunately reduces the feedback that can be provided, particularly where some are outliers. There were several participants that had washed the material but did not report a result (A2, D5, L6, M5 & T4). Many would have had a satisfactory result. There were six participants (K9, U3, Y3, N2, E7 & K2) that did not supply sufficient data to check the result obtained. This unfortunately reduces the feedback that can be provided, particularly where some are outliers. There were six outliers identified (Z3, Y6, D4, Q5, E4 & L7) where the participants need to investigate the result and one participant that should review their result (Y3). The results for Z3 and L7 were recalculated based on the masses provided and gave satisfactory results suggesting a calculation error had been made. There were several participants (L8, D4, Q5, L9, Y5, Q2 & X4) that had significant differences between the result reported and the recalculated value. In several cases there had been rounding of results as well as not reporting to the correct number of decimal places. Participant L7 was an outlier but showed up in section 3.1 as having an issue with overall calculations being correctly performed which may also account for the incorrect finer than 75 µm result. It is unclear from the data supplied the reason for E4’s outlier. 3.3 Particle shape by proportional calliper (2:1 & 3:1) Proportional calliper tests are most likely going to give a wide spread of results. The spread of results (variation) will depend on the particular grade of aggregate, time produced and manufacturer. The method of manufacturing aggregate has limited ability to control the particle shape. The coefficient of variation is typically around the 20% mark for 2:1 and higher for 3:1. The results normally would be taken as indicative. However the results are still important and useful. Participants’ with abnormally high or low results show up as outliers. The variation in results was considerably higher for this program (CV 40%) than the previous program (2016(68) CV 27%).



Several participants indicated that they did not have the prescribed 100 stones for the 13.2 mm fraction for the test. This was also observed in the homogeneity testing, table 3.3A, with results shown in blue. The variation was small for this test indicating that the overall sample was sufficiently homogenous and unlikely to be a significant part of the overall program variation shown by participants (40% CV). Table 3.3A also shows the results where only the 9.5 mm fraction is used in the calculation of the proportional calliper results. These gives a higher proportional calliper result. In view of the homogeneity data the spread in results shown by participants should have been smaller. The flat and elongated stones could also be visually assessed and appeared regular in the samples provided. Some stones are difficult to measure due to their shape. Participants need to be sure that the width and thickness are correctly identified. This accounts for some of the variation observed. Correct splitting of the sample to obtain the 100 or more stones is by far the most significant source of error or variation for this test. The sample needs to be well mixed and showing no signs of segregation prior to splitting. The number of stones used also has an impact. For homogeneity testing around 200 stones are used per fraction. Although outliers have been identified as detailed below, participants with proportional calliper test results under 10% or over 30 % should also review their methodology and compliance to the test method. There were two outliers identified (A2 & S6) for the 2:1 test and two for the 3:1 test (P5 & S6). These participants need to investigate the reason for the outlier. Those with particularly high z-scores (P5 & L4) for the 2:1 test and (T2 & Q3) for the 3:1 test should review their outcomes.

Units H1 H2 H3 H4 H5 H6 H7 H8 H9 Average s.d Coefficient

of Variation

Proportional Calliper 2:1 (Full)

% 20.4 22.5 22.0 18.2 23.3 20.1 21.8 19.1 20.9 20.9 1.6 7.9

Proportional Calliper 2:1 (9.5 only)

% 24.5 23.6 25.5 19.8 25.9 22.5 24.8 22.9 25.1 23.8 1.9 8.0

Table 3.3A Proportional calliper 2:1 homogeneity results. Blue shaded indicates less than 100

stones

Most participants had z-scores under ± 2. Overall the performance by participants was good for the proportional calliper test but there is room for improvement.



3.4 Flakiness Index Unlike grading the testers skill has little influence over the outcome of the test. Provided the test is performed correctly a tester should be able to retest each fraction and get essentially the same result. The spread of results observed is indicative of the manufacturing process rather than that of the participants. So, unlike the other tests the standard deviation should reflect the manufacturing process rather than the precision of the testers. The proficiency testing program therefore will only pick up gross departures from the median result. This is satisfactory from a proficiency program perspective; it just means that an outlier is outside both the testing confidence interval and the materials natural variation associated with production. The spread of results obtained for the flakiness test is generally less than the proportional calliper test. There were no outliers for this test with most participants having a z-score below ± 2 which is a very good outcome. It is reasonable however, for this test, to expect participants results to be very similar to the homogeneity test results. As this is not the case it suggests that the spread in results, while statistically satisfactory, may not be acceptable on a practical basis. Many participants may still need to improve in the performance of this test. Those participants with z-scores above 1.0 or below -1.0 may benefit from reviewing their test practice. This may involve checking that particles are not missed during the testing process. Particles that are more rounded may need to be manipulated several ways before it will eventually pass through the slot. Other aspects of the test methodology that may cause inaccurate results to be obtained include:

• Incorrect performance of PSD

• Failure to mix and split sample correctly

• Worn gauge

• Incorrect slot used

• Insufficient manipulation of stone to check all orientations

• Forcing stones through gauge

• Loss of stones, both before and during testing

• Incorrect weighing

• Balance inaccuracy



3.5 Average Least Dimensions

This test produced results with a small variation across the 54 participants who returned results for this test representing a very good outcome. Two outliers (X6 & W7) were identified. Two other participants (N9 & L7) high z-scores that should be reviewed. As with flakiness the tester’s skill should have little influence over the outcome of the test. Provided the test is performed correctly a tester should be able to retest the sample and get essentially the same result. The spread of results observed is indicative of the manufacturing process rather than that of the participants. So unlike the other tests the standard deviation reflects the manufacturing process rather than the precision of the testers. The proficiency testing program therefore will only pick up gross departures from the median result. This is satisfactory from a proficiency program perspective; it just means that any outlier is outside both the testing confidence interval and the materials natural variation associated with production.

Aggregate 2015(60) PT Program - ALD

Statistics All Slotted and

Vernier Slotted Vernier

Calculated (20.3)

No Participants 33 23 17 6 9

Average 8.0 7.8 7.8 7.9 7.7

Standard Deviation 0.6 0.6 0.5 0.9 2.9


Statistics All Slotted

and Vernier

Slotted Vernier Calculated

(20.3)


Average 8.2 8.2 8.1 8.4 9.2

Standard Deviation 0.8 0.8 0.8 0.8 -


Statistics All Flatbed Slotted Vernier Calculated

(20.3)


Average 8.1 8.0 7.7 8.0 9.1


Table 3.5A Comparison of ALD statistics for 2015, 2016 and 2017 programs



Consequently, both the homogeneity and participants results and statistics should be quite similar. However, it should be noted that it is very dependent on having a representative sample to begin with and how well the sample is split down to obtain the 100 or more stones needed for the test. The test method indicates 100 stones as a minimum. The higher the number of stones used the greater the confidence in the result obtained as well as reducing the impact of any stones incorrectly ‘sized’ during testing. Previous program have indicated that there is very little difference between using a slotted gauge or vernier callipers. Table 3.5A indicates the variation comparison. The statistics for this program yielded similar outcomes to the 2015 and 2016 program shown in Table 3.5A. Both sets of statistics have had the outliers removed.

Code

Average Least Dimensions

All Flatbed Slotted Vernier Calculated

(20.3)

A2 8.6 8.6

D5 7 7

L6 6.6 6.6

K9 9.3

P8 8.6 8.6

N9 10.8 10.8

T2 7.5 7.5

X6 12.79 12.79

G7 7.9 7.9

Q3 7.96 7.96

R5 7.7 7.7

U3 9.2 9.2

P5 9.1 9.1

G8 7.7 7.7

C2 10.3

F4 7.9 7.9

R4 7.6 7.6

N8 7.9 7.9

M2 7.4 7.4

G3 8 8

L8 7.7 7.7

Y3 7.8 7.8

N7 8.1 8.1

C5 9.3 9.3

V9 8.3 8.3

D4 8.2 8.2



J7 8.1 8.1

X8 7.8 7.8

U9 7.9 7.9

J8 7.6 7.6

S8 7.6 7.6

P3 7.4 7.4

D6 7.6 7.6

K7 7.3 7.3

G9 7.5 7.5

F8 7.9 7.9

E6 7.9 7.9

N2 9.1 9.1

W7 11.7 11.7

G6 8.1 8.1

T9 8 8

R2 7.1 7.1

L7 11 11

K3 7.7 7.7

S3 7.8 7.8

P7 9.6 9.6

K5 9.3 9.3

F7 9.6 9.6

L4 7.3 7.3

M4 7.4 7.4

E7 8

S6 9.1 9.1

X7 6.9

K2 9.1 9.1


Average 8.3 8.4 7.9 8.4 9.1

Standard Deviation

1.2 1.4 1.1 1.1 0.2

Table 3.5B ALD results. Outliers and results with high z-scores shown in blue.

Code

Average Least Dimensions

All Flatbed Slotted Vernier Calculated

(20.3)


Average 8.1 8.0 7.7 8.0 9.1


Table 3.5C ALD results less outliers



Method 20.3

Six participants choose to use the calculation method. Previous proficiency programs have indicated that there is little if any difference regardless of whether AS 1141: 20.1 or 20.3 is used. The homogeneity was undertaken using both the slotted gauge and calculation method. The calculation method tends to give rise to results that are higher than the slotted gauge but still close to one standard deviation of the median. This can be seen from table 3.5A and 3.5B as well. Care should be taken when reviewing these comparison as the numbers indicated for some categories (i.e. 20.3) are low. Despite the homogeneity displaying smaller variation for the calculated ALD (method 20.3), it may not be as accurate as using direct measurement (method 20.1). If the measurement uncertainty was to be calculated for both methods, it would be much larger for method 20.3 as it uses several other test results (parameters) to derive the ALD value (i.e. ‘% Passing’ and FI). A further draw back with method 20.3 is that any inaccuracies with the parameters used to calculate the ALD will affect the result obtained. 3.6 Apparent Particle Density

Particle Density on a Dry Basis

Particle Density on a Saturated-surface-dry Basis

The material used in this program was selected to give reasonably consistent results across all three tests. There were 48 participants that performed the tests to AS 1141.6.1. The tests involve operations that require skilled technicians to obtain accurate and consistent results. The test, as intended, is sensitive to surface irregularities and internal voids. However, the more surface irregularities the harder it is to determine the “surface dry” state. This may influence the spread of results observed depending on the skill level of the overall group of participants. The more homogenous the material under test (i.e. with the same surface and voids in each stone) the smaller the variation is likely to be. The affect can be seen in the increased variability compared to the 2013(45)-proficiency program (no voids), table 3.6A.



Particle density test

Program

Apparent density Dry basis SS dry basis

Median Normalised

IQR Median

Normalised IQR

Median Normalised

IQR

t/m3 t/m3 t/m3 t/m3 t/m3 t/m3

2013(45) 2.98 0.015 2.95 0.015 2.96 0.015

2014(49) 2.81 0.022 2.62 0.022 2.69 0.037

2015(60) 2.84 0.023 2.65 0.020 2.72 0.017

2016(68) 2.84 0.030 2.67 0.028 2.73 0.015

2017(75) 2.81 0.023 2.64 0.030 2.70 0.015

Table 3.6A Comparison of previous and current program statistics

Overall the variation was similar to previous programs. (Table 3.6A). The particle density on a saturated surface-dry basis was particularly good. The spread of results was within the range expected for this test. Of the 48 participants there were 17 outliers identified involving 8 participants (17%) for the density test only. Participants with outliers need to look at all three tests in relation to each other when reviewing the outcome as detailed in Table 3.6B. The z-scores across all three tests should also be considered.

Outliers for the particle density test

T4 L9 Y5 J8 E9 L4 G3 F4 Q2 (P7) (K5) (J7)

Apparent particle density

-11.3 -4.3 -4.7 -3.0 4.7 -71 -2.6 -1.3 -0.4 -2.2 -1.7 1.3

Particle density on a dry basis

-10.4 -2.6 0.9 -3.6 4.0 -68.4 -3.2 -2.7 2.7 -1.4 -1.8 1.8

Particle density on a saturated-surface dry basis

-16 -2.0 -1.4 -4.7 6.7 -105 -4.7 -3.4 2.7 -2.7 -2.7 2.7

Water Absorption

--0.2 -5.9 -5.9 0.2 0.1 -0.2 0.4 1.47 -4.1 -0.7 -0.4 -0.8

Table 3.6B Outliers (shown in bold) for the particle density test to AS 1141 – 6.1. Those in

brackets indicate high z-scores.



Four participants (T4, J8, E9 & L4) had outliers identified across all three tests. All results were on the low end (i.e. lower than the median value). This would indicate a possible systematic issue affecting all three tests possibly a calculation, rounding or weighing error. Material not being fully dried is another possibility. Similarly, participants (L9, Y5, G3 & F4) showed a similar trend towards low results. Possible sources of variation in results include:

• Transcription errors

• Incorrect calculations

• Weighing error

• Not removing 4.75 retained

• Trapped fines in basket. Need to remove fines after washing and absorption period – some stones break up.

• Insufficient washing

• Loss of stones during testing

• Basket touching side of bucket

• Incorrect taring of balance with bucket in water

• Over or under drying

• Incorrect temperature correction

• Sample not dry after drying to constant weight

• Trapped bubbles

• Stones trapped in basket

• Bucket not filled to the same spot with water

For particle density on ‘dry’ and ‘saturated-surface dry’ basis the drying to a ‘surface-dry’ state is critical to the accuracy of the test results. An outlier at either the low or high density may indicate either the material being too wet or too dry. Correct oven drying is also critical. 3.7 Water Absorption Forty-eight participants performed the test to AS 1141.6.1. There were three outliers identified (L9, Y5 & Q2) all with a very low absorption result. Insufficient oven drying (i.e. not achieving a constant mass) will cause a lower absorption result to be obtained. An error in calculations or the recording of a test parameter could have occurred. Allowing the material to be too dry as to when “Surface Dry” has been achieved would also cause a low result.



Participants with a low absorption values (i.e. below 2.0 %) have probably judged the “Surface Dry” condition as being too far on the dry side of “Surface Dry”. Variation in the performance of this test is strongly influenced by the skill of the tester (ability to determine surface dry) and the type of material under test (number of voids, porosity, etc). Performing the test in both a controlled environment and in the same manner is important. Changes in drying material or technique, temperature, wind, humidity and lighting can have a significant effect. Material with a “honey combed” appearance compared to smooth material will have a greater surface area and therefore influence the result obtained. It also makes it harder to determine “Surface Dry”. The spread is about what is normally attributed to this test. The variation (s.d) was 0.27 for this program compared to 0.37 for the 2016 and 0.21 for the 2015 program. Most participants were within ± 2 s.d which was a very good outcome. 3.8 Summary of test results (unrounded)

Test Units Participants Median Normalised

IQR

Particle size distribution (% Passing) 13.2 mm

% 92

62.2 0.96

9.5 mm 40.0 1.08

6.7 mm 10.1 0.69

4.75 mm 4.6 0.44

Material finer than 75 µm (by washing) % 84 2.77 0.31



Flakiness index % 63 8.40 1.45

Average least dimensions mm 54 7.90 1.11

Apparent particle density t/m3 48 2.81 0.023

Particle density on a dry basis t/m3 48 2.640 0.022

Particle density on a saturated-surface dry basis t/m3 47 2.700 0.015

Water absorption % 48 2.35 0.27



This page has been left blank intentionally.



P4 62.6 0.42 N8 61.3 -0.93 Q5 61.4 -0.83 E4 61.1 -1.14

A2 65 2.91 M2 61.6 -0.62 L9 62 -0.21 L7 62.0 -0.21

D5 63 0.83 B8 60.4 -1.87 Y5 62 -0.21 P6

L6 62 -0.21 J5 61.8 -0.42 J7 62.5 0.31 K3 60.40 -1.87

K9 62.0 -0.21 K6 64.0 1.87 A8 62.9 0.73 D8

M5 60.9 -1.35 F5 62.3 0.10 E6 61 -1.25 S3 62.2 0.00

P8 63 0.83 Q4 62.3 0.10 X8 63 0.83 M6 62 -0.21

C3 R9 61.25 -0.99 U9 63.1 0.93 P7 63.21 1.05

N9 62.2 0.00 Y4 62.3 0.10 J8 K5 63.82 1.68

T2 62.3 0.10 G3 62.5 0.31 L3 R6 61.9 -0.31

X6 62.7 0.52 W8 61.7 -0.52 A9 T8 60.8 -1.45

G7 63.8 1.66 X2 62.5 0.31 S8 63.2 1.04 X4 60.6 -1.66

A4 L8 63.2 1.04 P3 62.1 -0.10 B6 58.9 -3.42 #

Q3 62.7 0.52 D7 61.7 -0.52 D6 63.3 1.14 F7 61.6 -0.62

R5 65 2.91 B5 63.8 1.66 K7 62.2 0.00 E9 62 -0.21

W6 62.5 0.31 V8 62.1 -0.10 G9 62.9 0.73 L4 61 -1.25

S2 62.7 0.52 J2 64.25 2.13 F8 62.3 0.10 M4 63 0.83

B9 61.6 -0.62 Y3 63.0 0.83 Q2 63.3 1.14 E7 62 -0.21

U3 60.1 -2.18 N7 62.7 0.52 E5 62.8 0.62 S6 59.96 -2.32

P5 62.1 -0.10 T4 60.1 -2.18 B7 63.3 1.14 X7 61 -1.25

G8 62.6 0.42 Z3 62 -0.21 N2 63.7 1.56 K2 61.9 -0.31

C2 61.6 -0.62 Q7 62 -0.21 W7 61.7 -0.52

F4 64.6 2.49 Y6 61 -1.25 Y8 61.7 -0.52

M8 60.3 -1.97 C5 62 -0.21 G6 63.5 1.35

E3 62.9 0.73 V9 62.8 0.62 T9 63.3 1.14

R4 63.2 1.04 D4 62 -0.21 R2 62.3 0.10

Number of results 92

Median 62.2

Median MU 0.13

First Quartile 61.7

Third Quartile 63.0

IQR 1.30

Normalised IQR 0.96

CV (%) 1.5

Minimum 59.96 (58.90)

Maximum 65.00 (65.00)

Range 5.04 (6.10)

Code

Test

Result

%

Z Score

4.1 % Passing 13.2 mm: Z - Scores

Value

Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score

Note: A # indicates an outlier where the z-score obtained is either greater then 3 or less than -3. Codes for all

participates are shown. The results column shows a blank entry for those participants that did not submit a result

for this test. Minimum, Maximum and Range are calculated with outliers excluded, those in brackets include

outliers.

Statistic



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.1 % Passing 13.2 mm: Z - Score Graph

A2R5

F4J2

K6K5G7B5

N2G6

D6Q2B7T9

P7R4L8S8

U9D5 P8Y3X8M4E3A8G9

V9E5

X6Q3S2N7

P4G8

W6G3X2J7T2F5Q4Y4F8R2N9K7S3

P5V8P3L6K9Z3Q7C5D4L9Y5L7

M6E9E7R6K2

J5W8D7W7Y8

B9C2M2F7

Q5N8R9

E4Y6E6L4X7

M5T8

X4B8K3

M8U3T4

S6B6

-3 -2 -1 0 1 2 3



P4 40.0 0.00 N8 39.8 -0.19 Q5 37.7 -2.13 E4 37.8 -2.04

A2 42 1.85 M2 38.6 -1.30 L9 40 0.00 L7 39.1 -0.83

D5 40 0.00 B8 40.5 0.46 Y5 40 0.00 P6

L6 41 0.93 J5 39.7 -0.28 J7 40.0 0.00 K3 37.30 -2.50

K9 40.0 0.00 K6 41.6 1.48 A8 39.2 -0.74 D8

M5 39.6 -0.37 F5 40.0 0.00 E6 39 -0.93 S3 41.5 1.39

P8 41 0.93 Q4 41.1 1.02 X8 41 0.93 M6 40 0.00

C3 R9 39.78 -0.20 U9 41.5 1.39 P7 39.81 -0.18

N9 37.7 -2.13 Y4 40.5 0.46 J8 K5 41.30 1.21

T2 41.1 1.02 G3 39.6 -0.37 L3 R6 40.8 0.74

X6 40.6 0.56 W8 38.4 -1.48 A9 T8 37.4 -2.41

G7 42.9 2.69 X2 37.8 -2.04 S8 40.7 0.65 X4 38.7 -1.21

A4 L8 40.6 0.56 P3 40.2 0.19 B6 39.1 -0.83

Q3 40.4 0.37 D7 40.7 0.65 D6 39.1 -0.83 F7 39.6 -0.37

R5 41 0.93 B5 39.9 -0.09 K7 40.6 0.56 E9 40 0.00

W6 40.1 0.09 V8 39.6 -0.37 G9 41.3 1.21 L4 40 0.00

S2 40.2 0.19 J2 39.16 -0.78 F8 39.0 -0.93 M4 42 1.85

B9 39.2 -0.74 Y3 40.2 0.19 Q2 40.6 0.56 E7 40 0.00

U3 38.6 -1.30 N7 39.6 -0.37 E5 40.6 0.56 S6 39.49 -0.47

P5 40.1 0.09 T4 36.8 -2.97 B7 40.2 0.19 X7 38 -1.85

G8 40.3 0.28 Z3 38 -1.85 N2 40.3 0.28 K2 39.5 -0.46

C2 40.2 0.19 Q7 41 0.93 W7 39.0 -0.93

F4 41.6 1.48 Y6 38 -1.85 Y8 39.1 -0.83

M8 38.1 -1.76 C5 40 0.00 G6 40.5 0.46

E3 39.3 -0.65 V9 40.5 0.46 T9 41.0 0.93

R4 40.1 0.09 D4 39 -0.93 R2 40.4 0.37


Median 40.0

Median MU 0.14

First Quartile 39.1

Third Quartile 40.6

IQR 1.46

Normalised IQR 1.08

CV (%) 2.7

Minimum 36.8 ()

Maximum 42.9 ()

Range 6.1 ()

Code

Test

Result

%

Z Score


Value

Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score



for this test. Results in green have been calculated by the program coordinator. Minimum, Maximum and Range

are calculated with outliers excluded, those in brackets include outliers.

Statistic



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus


G7A2M4

F4K6

U9S3

G9K5

T2Q4L6P8R5Q7X8T9

R6D7S8

X6L8K7Q2E5

B8Y4V9G6

Q3R2G8N2S2C2Y3P3B7W6P5R4P4D5 K9F5C5L9Y5J7M6E9L4E7

B5P7N8R9J5

M5G3V8N7F7

K2S6

E3B9A8J2

D6Y8L7B6

D4E6F8

W7X4

U3M2

W8M8Z3Y6X7

X2E4

N9Q5

T8K3

T4

-3 -2 -1 0 1 2 3



P4 10.4 0.43 N8 10.6 0.72 Q5 7.6 -3.61 # E4 8.1 -2.89

A2 11 1.30 M2 9.8 -0.43 L9 11 1.30 L7 8.1 -2.89

D5 11 1.30 B8 10.1 0.00 Y5 12 2.74 P6

L6 11 1.30 J5 9.4 -1.01 J7 9.4 -1.01 K3 9.50 -0.87

K9 9.3 -1.15 K6 13.1 4.33 # A8 10.1 0.00 D8

M5 10.9 1.15 F5 9.4 -1.01 E6 11 1.30 S3 9.8 -0.43

P8 10 -0.14 Q4 10.6 0.72 X8 11 1.30 M6 10 -0.14

C3 R9 10.2 0.14 U9 11.5 2.02 P7 10.74 0.92

N9 8.5 -2.31 Y4 11.1 1.44 J8 K5 10.79 1.00

T2 10.7 0.87 G3 10.1 0.00 L3 R6 9.8 -0.43

X6 10.3 0.29 W8 10.1 0.00 A9 T8 9.0 -1.59

G7 10.3 0.29 X2 10.7 0.87 S8 11.1 1.44 X4 10.1 0.00

A4 L8 11.0 1.30 P3 10.9 1.15 B6 9.7 -0.58

Q3 9.9 -0.29 D7 11.8 2.45 D6 11.1 1.44 F7 10.3 0.29

R5 11 1.30 B5 10.5 0.58 K7 11 1.30 E9 10 -0.14

W6 9.9 -0.29 V8 9.7 -0.58 G9 11.2 1.59 L4 10 -0.14

S2 10.7 0.87 J2 9.80 -0.43 F8 8.2 -2.74 M4 10 -0.14

B9 10.3 0.29 Y3 10.6 0.72 Q2 10.4 0.43 E7 10 -0.14

U3 9.5 -0.87 N7 10.5 0.58 E5 10.2 0.14 S6 9.13 -1.40

P5 10.0 -0.14 T4 0.7 -13.6 # B7 10.6 0.72 X7 7 -4.47 #

G8 10.0 -0.14 Z3 8.5 -2.31 N2 10.2 0.14 K2 10.1 0.00

C2 8.5 -2.31 Q7 11 1.30 W7 9.9 -0.29

F4 11.5 2.02 Y6 8.0 -3.03 # Y8 10.0 -0.14

M8 9.6 -0.72 C5 9 -1.59 G6 10.3 0.29

E3 9.9 -0.29 V9 10.4 0.43 T9 10.5 0.58

R4 10.1 0.00 D4 9.0 -1.59 R2 10.4 0.43


Median 10.1

Median MU 0.09

First Quartile 9.8

Third Quartile 10.7

IQR 0.93

Normalised IQR 0.69

CV (%) 6.9

Minimum 8.1 (0.7)

Maximum 12.0 (13.1)

Range 3.9 (12.4)

Code

Test

Result

%

Z Score


Value

Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score





Statistic



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus


K6Y5D7F4U9G9Y4S8D6A2D5 L6R5L8Q7L9E6X8K7M5P3K5P7T2S2X2N8Q4Y3B7B5N7T9P4V9Q2R2X6G7B9G6F7R9E5N2R4B8G3W8A8X4K2

P8P5G8Y8

M6E9L4

M4E7Q3

W6E3

W7M2

J2S3R6V8B6

M8U3K3J5F5J7K9S6C5D4T8N9C2Z3F8E4L7Y6Q5X7T4

-3 -2 -1 0 1 2 3



P4 4.7 0.22 N8 4.7 0.22 Q5 2.6 -4.50 # E4 2.8 -4.05 #

A2 5 0.90 M2 4.4 -0.45 L9 4 -1.35 L7 2.4 -4.95 #

D5 5 0.90 B8 4.2 -0.90 Y5 5 0.90 P6

L6 6 3.15 # J5 4.6 0.00 J7 4.2 -0.90 K3 4.70 0.22

K9 4.2 -0.90 K6 7.9 7.42 # A8 4.9 0.67 D8

M5 5.1 1.12 F5 4.2 -0.90 E6 5 0.90 S3 4.7 0.22

P8 5 0.90 Q4 5.2 1.35 X8 5 0.90 M6 4.4 -0.45

C3 R9 4.46 -0.31 U9 5.1 1.12 P7 4.34 -0.58

N9 2.2 -5.40 # Y4 5.2 1.35 J8 K5 4.59 -0.02

T2 4.8 0.45 G3 4.4 -0.45 L3 R6 4.5 -0.22

X6 4.6 0.00 W8 5.0 0.90 A9 T8 4.3 -0.67

G7 4.5 -0.22 X2 5.1 1.12 S8 4.9 0.67 X4 4.8 0.45

A4 L8 5.1 1.12 P3 5.1 1.12 B6 4.6 0.00

Q3 4.6 0.00 D7 7.2 5.85 # D6 5 0.90 F7 4.5 -0.22

R5 5 0.90 B5 4.5 -0.22 K7 5.2 1.35 E9 4 -1.35

W6 5.0 0.90 V8 4.4 -0.45 G9 5.4 1.80 L4 5 0.90

S2 4.8 0.45 J2 3.98 -1.39 F8 2.4 -4.95 # M4 5 0.90

B9 4.6 0.00 Y3 5.1 1.12 Q2 4.5 -0.22 E7 5 0.90

U3 4.5 -0.22 N7 4.6 0.00 E5 4.8 0.45 S6 4.48 -0.27

P5 5.0 0.90 T4 0.6 -9.0 # B7 4.9 0.67 X7 2 -5.85 #

G8 4.6 0.00 Z3 2.7 -4.27 # N2 4.6 0.00 K2 4.6 0.00

C2 1.9 -6.07 # Q7 5 0.90 W7 4.6 0.00

F4 5.3 1.57 Y6 2.5 -4.72 # Y8 4.6 0.00

M8 3.6 -2.25 C5 5 0.90 G6 4.4 -0.45

E3 4.9 0.67 V9 4.7 0.22 T9 4.6 0.00

R4 4.5 -0.22 D4 5.0 0.90 R2 4.7 0.22


Median 4.6

Median MU 0.06

First Quartile 4.4

Third Quartile 5.0

IQR 0.60

Normalised IQR 0.44

CV (%) 9.7

Minimum 3.6 (0.6)

Maximum 5.4 (7.9)

Range 1.8 (7.3)





Statistic

Code

Test

Result

%

Z Score


Value

Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus


K6D7L6G9F4Q4Y4K7M5X2L8Y3U9P3A2D5 P8R5W6P5W8Q7C5D4Y5E6X8D6L4M4E7E3A8S8B7T2S2E5X4P4N8V9R2K3S3X6Q3B9G8J5N7N2W7Y8T9B6K2

K5G7U3R4B5Q2R6F7S6R9

M2G3V8G6

M6P7T8K9B8F5J7L9E9J2

M8E4Z3Q5Y6F8L7N9X7C2T4

-3 -2 -1 0 1 2 3



P4 2.80 0.10 N8 2.83 0.19 Q5 1.17 -5.11 # E4 0.81 -6.26 #

A2 NR M2 2.69 -0.26 L9 2.0 -2.46 L7 0.40 -7.57 #

D5 NR B8 2.35 -1.34 Y5 2 -2.46 P6

L6 NR J5 2.71 -0.19 J7 2.39 -1.21 K3 2.81 0.13

K9 2.46 -0.99 K6 2.81 0.13 A8 3.00 0.73 D8

M5 F5 2.49 -0.89 E6 2.89 0.38 S3 3.51 2.36

P8 2.61 -0.51 Q4 3.39 1.98 X8 3.29 1.66 M6 2.50 -0.86

C3 R9 2.80 0.10 U9 2.89 0.38 P7 2.48 -0.93

N9 3.27 1.60 Y4 3.23 1.47 J8 3.12 1.12 K5 2.73 -0.13

T2 2.52 -0.80 G3 2.51 -0.83 L3 R6 2.68 -0.29

X6 2.37 -1.28 W8 3.21 1.40 A9 T8 2.55 -0.70

G7 2.5 -0.86 X2 3.40 2 S8 NR X4 3.1 1.05

A4 L8 3.50 2.33 P3 2.82 0.16 B6 2.75 -0.06

Q3 2.27 -1.60 D7 3.39 1.98 D6 2.55 -0.70 F7 2.5 -0.86

R5 2.7 -0.22 B5 2.67 -0.32 K7 2.70 -0.22 E9 2.61 -0.51

W6 2.44 -1.05 V8 NR G9 2.81 0.13 L4 3.1 1.05

S2 2.49 -0.89 J2 NR F8 2.78 0.03 M4 2.84 0.22

B9 2.77 0.00 Y3 3.66 2.84 Q2 2.8 0.10 E7 3 0.73

U3 2.72 -0.16 N7 2.7 -0.22 E5 2.94 0.54 S6 2.81 0.13

P5 2.63 -0.45 T4 NR B7 3.02 0.80 X7 3.39 1.98

G8 2.61 -0.51 Z3 0.8 -6.29 # N2 2.82 0.16 K2 2.77 0.00

C2 3.19 1.34 Q7 2.90 0.42 W7 2.88 0.35

F4 3.26 1.56 Y6 0.8 -6.29 # Y8 2.89 0.38

M8 NR C5 2.80 0.10 G6 2.39 -1.21

E3 2.60 -0.54 V9 2.80 0.10 T9 2.76 -0.03

R4 2.68 -0.29 D4 4.00 3.93 # R2 2.94 0.54


Median 2.77

Median MU 0.04

First Quartile 2.52

Third Quartile 2.94

IQR 0.42

Normalised IQR 0.31

CV (%)

Minimum 2.00 (0.40)

Maximum 3.66 (4.0)

Range 1.66 (3.6)


participates are shown. The results column shows a blank entry for those participants that did not submit a

result for this test. Results in green have been calculated by the program coordinator. Minimum, Maximum

and Range are calculated with outliers excluded, those in brackets include outliers.

Statistic

11.3

Code

Test

Result

%

Z Score

4.2 Material finer than 75 µm: Z - Scores

Value

Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.2 Material finer than 75 µm: Z - Score Graph

D4Y3S3L8X2Q4D7X7X8N9F4Y4W8C2J8X4L4B7A8E7E5R2Q7E6U9Y8W7M4N8P3N2K6G9K3S6P4R9C5V9Q2F8B9K2

T9B6K5U3J5R5N7K7M2R4R6B5P5P8G8E9E3D6T8T2G3G7M6F7S2F5P7K9W6J7G6X6B8Q3L9Y5Q5E4Z3Y6L7

-3 -2 -1 0 1 2 3



P4 NR N8 NR Q5 NR E4 NR

A2 35.2 3.48 # M2 15.0 0.06 L9 7 -1.29 L7 21.9 1.23

D5 15.8 0.19 B8 9.4 -0.89 Y5 8 -1.13 P6

L6 9.5 -0.87 J5 11.8 -0.48 J7 NR K3 NR

K9 NR K6 NR A8 NR D8

M5 F5 NR E6 2.3 -2.09 S3 9.2 -0.92

P8 NR Q4 NR X8 11.1 -0.60 M6 13.0 -0.28

C3 R9 NR U9 13.9 -0.13 P7 16.8 0.36

N9 11.1 -0.60 Y4 NR J8 13.8 -0.14 K5 17.2 0.43

T2 NR G3 17.0 0.40 L3 R6 NR

X6 12.04 -0.44 W8 NR A9 T8 NR

G7 24.2 1.62 X2 NR S8 23.6 1.51 X4 NR

A4 L8 7.9 -1.14 P3 NR B6 NR

Q3 10.12 -0.77 D7 NR D6 NR F7 NR

R5 17.8 0.53 B5 NR K7 NR E9 NR

W6 NR V8 NR G9 NR L4 30.4 2.67

S2 NR J2 NR F8 NR M4 6.1 -1.45

B9 NR Y3 NR Q2 NR E7 14 -0.11

U3 19.5 0.82 N7 9.4 -0.89 E5 23.8 1.55 S6 49 5.81 #

P5 30.3 2.65 T4 NR B7 19.7 0.85 X7 NR

G8 5.3 -1.58 Z3 18.0 0.57 N2 NR K2 18.0 0.57

C2 NR Q7 NR W7 NR

F4 NR Y6 NR Y8 NR

M8 NR C5 14.0 -0.11 G6 18.6 0.67

E3 18.3 0.62 V9 14.3 -0.06 T9 13.1 -0.26

R4 16.9 0.38 D4 NR R2 24.9 1.73


Median 14.7

Median MU 1.11

First Quartile 10.9

Third Quartile 18.8

IQR 8.0

Normalised IQR 5.9

CV (%) 40

Minimum 2.3 (2.3)

Maximum 30.4 (49.0)

Range 28.1 (46.7)



result for this test. Minimum, Maximum and Range are calculated with outliers excluded, those in brackets

include outliers.

Statistic

Code

Test

Result

%

Z Score

4.3 Particle Shape - Proportional Calliper (2:1): Z - Scores

Value

Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.3 Particle Shape - Proportional Calliper (2:1): Z - Score Graph

S6

A2

L4

P5

R2

G7

E5

S8

L7

B7

U3

G6

E3

Z3

K2

R5

K5

G3

R4

P7

D5

M2

V9

C5

E7

U9

J8

T9

M6

X6

J5

N9

X8

Q3

L6

B8

N7

S3

Y5

L8

L9

M4

G8

E6

-3 -2 -1 0 1 2 3



P4 NR N8 NR Q5 NR E4 NR

A2 3.5 2.05 M2 0.3 -0.47 L9 1 0.08 L7 1.6 0.55

D5 4.1 2.52 B8 0.0 -0.71 Y5 1 0.08 P6

L6 0 -0.71 J5 0.3 -0.47 J7 0.5 -0.32 K3 NR

K9 NR K6 NR A8 NR D8

M5 F5 NR E6 0.3 -0.47 S3 0.7 -0.16

P8 NR Q4 NR X8 0.4 -0.39 M6 2.9 1.58

C3 R9 NR U9 0.4 -0.39 P7 1.8 0.71

N9 0.9 0.00 Y4 NR J8 0.7 -0.16 K5 2.0 0.87

T2 4.4 2.76 G3 0.2 -0.55 L3 R6 NR

X6 0.35 -0.43 W8 NR A9 T8 NR

G7 3.8 2.28 X2 NR S8 1.0 0.08 X4 NR

A4 L8 0.5 -0.32 P3 NR B6 NR

Q3 4.55 2.88 D7 NR D6 NR F7 NR

R5 0.0 -0.71 B5 NR K7 NR E9 NR

W6 NR V8 NR G9 NR L4 2.8 1.50

S2 NR J2 NR F8 NR M4 0.1 -0.63

B9 NR Y3 NR Q2 NR E7 1 0.08

U3 0.9 0.00 N7 0.4 -0.39 E5 2.5 1.26 S6 12 8.74 #

P5 7.6 5.28 # T4 NR B7 1.7 0.63 X7 NR

G8 0.7 -0.16 Z3 0 -0.71 N2 NR K2 0.8 -0.08

C2 NR Q7 NR W7 NR

F4 NR Y6 NR Y8 NR

M8 NR C5 0.0 -0.71 G6 2.1 0.95

E3 1.1 0.16 V9 1.2 0.24 T9 0.6 -0.24

R4 0 -0.71 D4 NR R2 2.8 1.50


Median 0.90

Median MU 0.23

First Quartile 0.36

Third Quartile 2.08

IQR 1.71

Normalised IQR 1.27

CV (%)

Minimum 0.0 (0.0)

Maximum 4.6 (12.0)

Range 4.6 (12.0)




include outliers.

Statistic

141

Code

Test

Result

%

Z Score

4.4 Particle Shape - Proportional Calliper (3:1): Z - Scores

Value

Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.4 Particle Shape - Proportional Calliper (3:1): Z - Score Graph

S6

P5

Q3

T2

D5

G7

A2

M6

R2

L4

E5

G6

K5

P7

B7

L7

V9

E3

L9

Y5

S8

E7

N9

U3

K2

G8

J8

S3

T9

L8

J7

N7

X8

U9

X6

M2

J5

E6

G3

M4

L6

R5

R4

B8

Z3

C5

-3 -2 -1 0 1 2 3



P4 7.5 -0.62 N8 11.7 2.28 Q5 NR E4 NR

A2 10.8 1.66 M2 NR L9 NR L7 10.1 1.18

D5 10.3 1.31 B8 7.3 -0.76 Y5 NR P6

L6 10.3 1.31 J5 NR J7 7.8 -0.42 K3 NR

K9 8.0 -0.28 K6 NR A8 8.5 0.07 D8

M5 F5 NR E6 7 -0.97 S3 7.8 -0.42

P8 11.5 2.14 Q4 NR X8 6.6 -1.25 M6 9.3 0.62

C3 R9 NR U9 8.2 -0.14 P7 4.8 -2.49

N9 8.4 0.00 Y4 NR J8 7.1 -0.90 K5 5.9 -1.73

T2 9.2 0.55 G3 8.4 0.00 L3 R6 11.4 2.08

X6 8.8 0.28 W8 NR A9 T8 NR

G7 9.5 0.76 X2 10.2 1.25 S8 7.1 -0.90 X4 NR

A4 L8 6.7 -1.18 P3 NR B6 NR

Q3 10.4 1.38 D7 NR D6 NR F7 9.3 0.62

R5 NR B5 8.3 -0.07 K7 NR E9 NR

W6 8.0 -0.28 V8 8.1 -0.21 G9 NR L4 8.5 0.07

S2 11.0 1.80 J2 6.6 -1.25 F8 NR M4 5.4 -2.08

B9 10.8 1.66 Y3 5.0 -2.35 Q2 NR E7 9 0.42

U3 9.5 0.76 N7 9.9 1.04 E5 5.7 -1.87 S6 NR

P5 8.9 0.35 T4 5 -2.35 B7 8.0 -0.28 X7 7 -0.97

G8 8.9 0.35 Z3 9.0 0.42 N2 9.1 0.48 K2 11.6 2.21

C2 9.2 0.55 Q7 10.0 1.11 W7 7.6 -0.55

F4 8.3 -0.07 Y6 8.0 -0.28 Y8 NR

M8 NR C5 9.5 0.76 G6 7.4 -0.69

E3 8 -0.28 V9 7.7 -0.48 T9 9.1 0.48

R4 9.1 0.48 D4 8 -0.28 R2 NR


Median 8.40

Median MU 0.23

First Quartile 7.55

Third Quartile 9.50

IQR 1.95

Normalised IQR 1.45

CV (%) 17

Minimum 4.8 ()

Maximum 11.7 ()

Range 6.9 ()




include outliers.

Statistic

Code

Test

Result

%

Z Score

4.5 Flakiness index: Z - Scores

Value

Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.5 Flakiness index: Z - Score Graph

N8K2

P8R6

S2A2B9

Q3D5 L6

X2L7

Q7N7

G7U3C5

M6F7

T2C2

R4N2T9

Z3E7

P5G8X6A8L4N9G3

F4B5U9V8K9

W6E3Y6D4B7J7S3

V9W7P4

G6B8

J8S8

E6X7

L8J2X8

K5E5

M4Y3T4

P7

-3 -2 -1 0 1 2 3



P4 NR N8 7.9 0.00 Q5 NR E4 NR

A2 8.6 0.63 M2 7.4 -0.45 L9 NR L7 11.0 2.79

D5 7.0 -0.81 B8 NR Y5 NR P6

L6 6.6 -1.17 J5 NR J7 8.1 0.18 K3 7.70 -0.18

K9 9.3 1.26 K6 NR A8 NR D8

M5 F5 NR E6 NR S3 7.8 -0.09

P8 8.6 0.63 Q4 NR X8 7.8 -0.09 M6 NR

C3 R9 NR U9 7.9 0.00 P7 9.6 1.53

N9 10.8 2.61 Y4 NR J8 7.6 -0.27 K5 9.3 1.26

T2 7.5 -0.36 G3 8.0 0.09 L3 R6 NR

X6 12.79 4.40 # W8 NR A9 T8 NR

G7 7.9 0.00 X2 NR S8 7.6 -0.27 X4 NR

A4 L8 7.7 -0.18 P3 7.4 -0.45 B6 NR

Q3 7.96 0.05 D7 NR D6 7.6 -0.27 F7 9.6 1.53

R5 7.7 -0.18 B5 NR K7 7.3 -0.54 E9 NR

W6 NR V8 NR G9 7.5 -0.36 L4 7.3 -0.54

S2 NR J2 NR F8 7.9 0.00 M4 7.4 -0.45

B9 NR Y3 7.8 -0.09 Q2 NR E7 8.0 0.09

U3 9.2 1.17 N7 8.1 0.18 E5 7.9 0.00 S6 9.1 1.08

P5 9.1 1.08 T4 NR B7 NR X7 6.9 -0.90

G8 7.7 -0.18 Z3 NR N2 9.1 1.08 K2 9.1 1.08

C2 10.3 2.16 Q7 NR W7 11.7 3.42 #

F4 7.9 0.00 Y6 NR Y8 NR

M8 NR C5 9.3 1.26 G6 8.1 0.18

E3 NR V9 8.3 0.36 T9 8.0 0.09

R4 7.6 -0.27 D4 8.2 0.27 R2 7.1 -0.72


Median 7.90

Median MU 0.19

First Quartile 7.60

Third Quartile 9.10

IQR 1.50

Normalised IQR 1.11

CV (%) 14.1

Minimum 6.6 (6.6)

Maximum 11.0 (12.79)

Range 4.4 (6.2)

Code

Test

Result

mm

Z Score

4.6 Average least dimensions: Z - Scores

Value

Code

Test

Result

mm

Z Score Code

Test

Result

mm

Z Score Code

Test

Result

mm

Z Score




include outliers.

Statistic



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.6 Average least dimensions: Z - Score Graph

X6

W7L7

N9C2

P7

F7K9

C5K5

U3P5N2

S6

K2A2P8

V9D4

N7J7

G6G3T9E7Q3

G7F4

N8U9F8

E5Y3

X8S3

R5G8L8

K3R4

J8S8D6T2G9

M2

P3M4K7L4

R2

D5 X7

L6

-3 -2 -1 0 1 2 3



P4 NR N8 2.81 0.00 Q5 NR E4 NR

A2 NR M2 2.82 0.43 L9 2.71 -4.32 # L7 2.81 0.00

D5 NR B8 2.80 -0.43 Y5 2.70 -4.75 # P6

L6 NR J5 NR J7 2.84 1.30 K3 NR

K9 NR K6 NR A8 2.84 1.30 D8

M5 F5 NR E6 2.82 0.43 S3 2.81 0.00

P8 NR Q4 2.83 0.86 X8 2.84 1.30 M6 2.83 0.86

C3 R9 NR U9 2.81 0.00 P7 2.76 -2.16

N9 NR Y4 NR J8 2.74 -3.02 # K5 2.77 -1.73

T2 NR G3 2.75 -2.59 L3 R6 NR

X6 NR W8 NR A9 T8 NR

G7 2.82 0.43 X2 NR S8 2.81 0.00 X4 NR

A4 L8 2.80 -0.43 P3 NR B6 NR

Q3 NR D7 NR D6 NR F7 NR

R5 2.804 -0.26 B5 NR K7 NR E9 2.92 4.75 #

W6 NR V8 NR G9 NR L4 1.15 -71.7 #

S2 NR J2 NR F8 NR M4 2.81 0.00

B9 NR Y3 2.83 0.86 Q2 2.80 -0.43 E7 2.82 0.43

U3 NR N7 2.81 0.00 E5 2.80 -0.43 S6 2.83 0.86

P5 NR T4 2.548 -11.3 # B7 2.84 1.30 X7 NR

G8 2.795 -0.65 Z3 2.85 1.73 N2 2.83 0.86 K2 2.82 0.43

C2 2.82 0.43 Q7 2.79 -0.86 W7 NR

F4 2.78 -1.30 Y6 NR Y8 NR

M8 2.84 1.30 C5 2.81 0.00 G6 2.85 1.73

E3 2.81 0.00 V9 2.82 0.43 T9 2.80 -0.43

R4 2.79 -0.86 D4 NR R2 2.81 0.00


Median 2.81

Median MU 0.004

First Quartile 2.80

Third Quartile 2.83

IQR 0.031

Normalised IQR 0.023

CV (%)

Minimum 2.75 (1.15)

Maximum 2.85 (2.92)

Range 0.10 (1.77)




outliers.

Statistic

0.8

Code

Test

Result

t/m3

Z Score

4.7 Apparent particle density: Z - Scores

Value

Code

Test

Result

t/m3

Z Score Code

Test

Result

t/m3

Z Score Code

Test

Result

t/m3

Z Score



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.7 Apparent particle density: Z - Score Graph

E9

Z3

G6

M8

J7

A8

X8

B7

Q4

Y3

N2

M6

S6

G7

C2

M2

V9

E6

E7

K2

E3

N8

N7

C5

U9

S8

R2

L7

S3

M4

R5

B8

L8

Q2

E5

T9

G8

R4

Q7

F4

K5

P7

G3

J8

L9

Y5

T4

L4

-3 -2 -1 0 1 2 3



P4 NR N8 2.66 0.90 Q5 NR E4 NR

A2 NR M2 2.64 0.00 L9 2.65 0.45 L7 2.68 1.80

D5 NR B8 2.63 -0.45 Y5 2.66 0.90 P6

L6 NR J5 NR J7 2.68 1.80 K3 NR

K9 NR K6 NR A8 2.62 -0.90 D8

M5 F5 NR E6 2.64 0.00 S3 2.64 0.00

P8 NR Q4 2.66 0.90 X8 2.63 -0.45 M6 2.65 0.45

C3 R9 NR U9 2.66 0.90 P7 2.61 -1.35

N9 NR Y4 NR J8 2.56 -3.60 # K5 2.60 -1.80

T2 NR G3 2.57 -3.15 # L3 R6 NR


G7 2.62 -0.90 X2 NR S8 2.65 0.45 X4 NR

A4 L8 2.63 -0.45 P3 NR B6 NR


R5 2.642 0.09 B5 NR K7 NR E9 2.73 4.05 #

W6 NR V8 NR G9 NR L4 1.12 -68.3 #

S2 NR J2 NR F8 NR M4 2.64 0.00

B9 NR Y3 2.63 -0.45 Q2 2.70 2.70 E7 2.66 0.90

U3 NR N7 2.67 1.35 E5 2.65 0.45 S6 2.63 -0.45

P5 NR T4 2.409 -10.4 # B7 2.67 1.35 X7 NR

G8 2.592 -2.16 Z3 2.65 0.45 N2 2.65 0.45 K2 2.66 0.90

C2 2.64 0.00 Q7 2.63 -0.45 W7 NR

F4 2.58 -2.70 Y6 NR Y8 NR

M8 2.63 -0.45 C5 2.63 -0.45 G6 2.64 0.00

E3 2.64 0.00 V9 2.63 -0.45 T9 2.66 0.90

R4 2.64 0.00 D4 NR R2 2.62 -0.90


Median 2.640

Median MU 0.004

First Quartile 2.630

Third Quartile 2.660

IQR 0.030


CV (%)

Minimum 2.58 (1.12)

Maximum 2.70 (2.73)

Range 0.12 (1.61)

Code

Test

Result

t/m3

Z Score

4.8 Particle density on a dry basis: Z - Scores

Value

Code

Test

Result

t/m3

Z Score Code

Test

Result

t/m3

Z Score Code

Test

Result

t/m3

Z Score




outliers.

Statistic

0.8



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.8 Particle density on a dry basis: Z - Score Graph

E9

Q2

J7

L7

N7

B7

N8

Q4

Y5

U9

T9

E7

K2

Z3

L9

S8

E5

N2

M6

R5

C2

E3

R4

M2

E6

G6

S3

M4

M8

B8

L8

Y3

Q7

C5

V9

X8

S6

G7

A8

R2

P7

K5

G8

F4

G3

J8

T4

L4

-3 -2 -1 0 1 2 3



P4 NR N8 2.71 0.67 Q5 NR E4 NR

A2 NR M2 2.70 0.00 L9 2.67 -2.02 L7 2.73 2.02

D5 NR B8 2.69 -0.67 Y5 2.68 -1.35 P6

L6 NR J5 NR J7 2.74 2.70 K3 NR

K9 NR K6 NR A8 2.70 0.00 D8

M5 F5 NR E6 2.71 0.67 S3 2.70 0.00

P8 NR Q4 2.72 1.35 X8 2.71 0.67 M6 2.71 0.67

C3 R9 NR U9 2.71 0.67 P7 2.66 -2.70

N9 NR Y4 NR J8 2.63 -4.72 # K5 2.66 -2.70

T2 NR G3 2.63 -4.72 # L3 R6 NR


G7 2.69 -0.67 X2 NR S8 2.71 0.67 X4 NR

A4 L8 2.69 -0.67 P3 NR B6 NR


R5 2.699 -0.07 B5 NR K7 NR E9 2.80 6.74 #

W6 NR V8 NR G9 NR L4 1.14 -105 #

S2 NR J2 NR F8 NR M4 2.70 0.00

B9 NR Y3 2.70 0.00 Q2 2.74 2.70 E7 2.72 1.35

U3 NR N7 2.72 1.35 E5 2.70 0.00 S6 2.70 0.00

P5 NR T4 2.463 -16.0 # B7 2.73 2.02 X7 NR

G8 2.664 -2.43 Z3 NR N2 2.71 0.67 K2 2.72 1.35

C2 2.70 0.00 Q7 2.69 -0.67 W7 NR

F4 2.65 -3.37 # Y6 NR Y8 NR

M8 2.70 0.00 C5 2.69 -0.67 G6 2.72 1.35

E3 2.70 0.00 V9 2.70 0.00 T9 2.71 0.67

R4 2.69 -0.67 D4 NR R2 2.69 -0.67


Median 2.700

Median MU 0.003

First Quartile 2.690

Third Quartile 2.710

IQR 0.020


CV (%) 0.5

Minimum 2.66 (1.14)

Maximum 2.74 (2.80)

Range 0.08 (1.66)

Code

Test

Result

t/m3

Z Score

4.9 Particle density on a saturated - surface dry basis: Z - Scores

Value

Code

Test

Result

t/m3

Z Score Code

Test

Result

t/m3

Z Score Code

Test

Result

t/m3

Z Score




outliers.

Statistic



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.9 Particle density on a saturated - surface dry basis: Z - Score Graph

E9

J7

Q2

B7

L7

Q4

N7

G6

E7

K2

N8

E6

X8

U9

S8

N2

T9

M6

C2

M8

E3

M2

Y3

V9

A8

E5

S3

M4

S6

R5

G7

R4

B8

L8

Q7

C5

R2

Y5

L9

G8

P7

K5

F4

G3

J8

T4

L4

-3 -2 -1 0 1 2 3



P4 NR N8 2.06 -1.09 Q5 NR E4 NR

A2 NR M2 2.41 0.23 L9 0.8 -5.85 # L7 1.81 -2.04

D5 NR B8 2.43 0.30 Y5 0.8 -5.85 # P6

L6 NR J5 NR J7 2.15 -0.75 K3 NR

K9 NR K6 NR A8 2.90 2.08 D8

M5 F5 NR E6 2.40 0.19 S3 2.32 -0.11

P8 NR Q4 2.16 -0.72 X8 2.74 1.47 M6 2.44 0.34

C3 R9 NR U9 1.97 -1.43 P7 2.16 -0.72

N9 NR Y4 NR J8 2.40 0.19 K5 2.24 -0.42

T2 NR G3 2.47 0.45 L3 R6 NR


G7 2.6 0.94 X2 NR S8 2.18 -0.64 X4 NR

A4 L8 2.40 0.19 P3 NR B6 NR


R5 2.18 -0.64 B5 NR K7 NR E9 2.38 0.11

W6 NR V8 NR G9 NR L4 2.3 -0.19

S2 NR J2 NR F8 NR M4 2.28 -0.26

B9 NR Y3 2.73 1.43 Q2 1.27 -4.08 # E7 2.1 -0.94

U3 NR N7 1.89 -1.74 E5 2.00 -1.32 S6 2.6 0.94

P5 NR T4 2.3 -0.19 B7 2.21 -0.53 X7 NR

G8 2.73 1.43 Z3 2.7 1.32 N2 2.38 0.11 K2 2.07 -1.06

C2 2.46 0.42 Q7 2.20 -0.57 W7 NR

F4 2.74 1.47 Y6 NR Y8 NR

M8 2.81 1.74 C5 2.50 0.57 G6 2.76 1.55

E3 2.38 0.11 V9 2.5 0.57 T9 1.94 -1.55

R4 2.12 -0.87 D4 NR R2 2.63 1.06


Median 2.35

Median MU 0.048

First Quartile 2.14

Third Quartile 2.50

IQR 0.36

Normalised IQR 0.27

CV (%) 11.3

Minimum 1.81 (0.80)

Maximum 2.90 (2.90)

Range 1.09 (2.10)

Code

Test

Result

%

Z Score

4.10 Water absorption: Z - Scores

Value

Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score Code

Test

Result

%

Z Score




outliers.

Statistic



ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.10 Water absorption: Z - Score Graph

A8

M8

G6

F4

X8

G8

Y3

Z3

R2

G7

S6

C5

V9

G3

C2

M6

B8

M2

L8

E6

J8

E3

N2

E9

S3

T4

L4

M4

K5

B7

Q7

R5

S8

Q4

P7

J7

R4

E7

K2

N8

E5

U9

T9

N7

L7

Q2

L9

Y5

-3 -2 -1 0 1 2 3



5. Program Information

5.1 Z-score Summary The proficiency program was conducted over October and November 2017. A ‘Z-score Summary’ summary was issued on the 22 January 2018 and posted on the LabSmart Services web site. The summary was also e-mailed to participants. The summary is intended as an early indicator of participant performance. The proficiency testing program report supersedes the z –score summary. Further information can be found in section 5.9 ‘Statistics’. Several additional results were added to the pool of participants results after the z-score summary was issued. The statistics shown in this, the final report, will consequently differ slightly to those shown in the z-score summary report. The performance outcomes however shown in both reports remain the same. The same participants that had outliers in the z-score summary have the same outliers in the final report.

5.2 Program Design 5.2.1 Design

It is expected that the level of experience/skill need to perform these tests will present a reasonable assessment of the overall competency of the tester and industry performance. Part of the design of each program involves determining what information needs to be requested to allow for the correct analysis of the data collected. This allows the best possible feedback to be offered to enable participants to improve in the performance of this test. The ‘retained weights’ for PSD is used for this purpose. In designing a proficiency program, it is sometimes necessary to minimise the effect of some inherent test method variability. Sufficient sample was provided to allow a large sample size to reduce the variability associated with variable sample size. Unaccounted material losses or gains (lost material, binding, material break down etc) have a greater effect the smaller the sample size. Other considerations involving the design of the program are detailed below. 5.2.2 Selection of material used in the program

Materials are selected to mirror the range of materials encountered in practice. Participants who work in a quarry may find that the material supplied is different to what they normally test. The test method does not stipulate a particular ‘quality of material’ be used for testing purposes so all testers need to be able to test accurately a range of aggregate materials.



The material supplied was made up of known fractions. See sample preparation (section 5.3) for more detail. The fractions were as large as possible to ensure any breakdown of material was small compared to the retained mass. In addition, as all participants had the same proportion of material then any breakdown of material while under test would be similar across all participants. Two samples (A & B) were used. Each had different fractions so that if the samples were mixed up by a participant the samples could be readily identified. See sample preparation (section 5.3) for more detail. 5.2.3 Role of proficiency testing

The determination of outliers is an important task of this proficiency program. A secondary function is to provide feedback that can help those with outliers identify possible areas to investigate as well as assist all participants to improve. In addition to the statistics, proficiency programs often obtain other information that is not normally available to a laboratory. It allows for a better understanding of the testing and can provide information that can lead to improvements in the testing process or test method. Proficiency testing enables participants to measure competency against others. It is also a measure of staff performance and the equipment used. Apart from ‘measurement uncertainty’ it is the most useful tool a laboratory has in better understanding the performance of a test. 5.2.4 Participant assessment

Assessment of each participant is based on a z-score that is related to the program consensus value (median). This is used to determine any statistical outliers. Compliance to proficiency program requirements including the correct calculation of results and adherence to program and test method requirements may also be used as part of the assessment process. Participants may also be asked to investigate any discrepancies detected with the paperwork submitted. 5.2.5 Reporting of results - Significant figures

The number of decimal places (significant figures) reported for a test has a bearing on the statistical analysis and therefore the interpretation of the results. There is a need to strike a balance between what is desirable from a statistical viewpoint while recognising how the results are used in practice. Too few decimal places (e.g. due to rounding) can cause an increase in the observed spread of results. Increasing the number of decimal places (with respect to normal reporting) can distort the observed spread of results compared to that encountered in actual practice. Large numbers of similar, rounded results can also cause a distortion in the analysis. For example, rounding to 0.5 % means that any number between 10.75 and 11.25 will be 11.0%. If the largest value is 10.75 in a set of results it is pushed out to 11.0 through rounding. Rounded results are useful from “an end user”



perspective but are not as useful when considering laboratory performance. The test method acknowledges additional decimal places may be used for statistical purposes. For this program, it was decided that the benefits of using additional decimal places would complement the aim of the proficiency program. Participants results were analysed as received regardless of whether there were ‘more or less’ significant figures than the number requested by the program. 5.2.6 Additional information requested

This program requested additional information as detailed in Appendix C not usually reported. The additional information is however consistent with the performance of the test and the records the test method requires laboratories to maintain. The additional information is used to interpret participant’s performance and assist with providing technical comment including feedback on outliers and possible participant improvement. 5.2.7 PSD data checks

A secondary function of proficiency testing is to provide feedback that can help those with outliers identify possible areas to investigate as well as assist all participants to improve. This information also helps with identifying any random or systematic errors associated with the test methodology. Every participant’s PSD results are recalculated. Checks however are only as accurate as the raw data supplied by each participant. These checks also help ensure that the data is comparable. Any inconsistencies identified during this process do not need to be investigated (as do outliers) but are identified as possible feedback for participant improvement. 5.2.8 Role of % Retained

The sieving component of this proficiency program is based on ‘% Passing’ results as normally reported by laboratories. The ‘% Passing’ involves a cumulative calculation which can at times give rise to misleading outliers, particularly on smaller aperture sieves. In such cases an outlier may not necessarily be attributed to the sieve size on which the outlier occurred. Participants need to be aware of this should they need to undertake any investigation. To provide feedback ‘% Retained’ is normally either requested or calculated for each participant (Appendix C). Increasing the number of significant numbers that results are reported also aids accurate analysis and feedback. It should be noted that if the mass retained results submitted are themselves not correct then this will show as z-scores greater than 3. This may be the case even if no outlier was obtained for the % passing results. To perform a comparison there needs to be a ‘one for one’ % passing correspondence to the



% retained for the analysis to be statistically valid. That is the accuracy of the analysis is dependent on most participants suppling mass retained results. 5.3 Sample Preparation Two samples were prepared (A & B). Sample A consisted of approximately 1.5 kg while sample B consisted of 3 kg of aggregate. An unwashed bulk sample was obtained and sieved into its constituent fractions. Each fraction was then thoroughly mixed. 110 samples were prepared in the laboratory by weighing out set fractions of a known weight and bagged. Sample B was prepared in a similar way but with different fractions. Samples were numbered and laid out in the order prepared. Ten samples were selected at approximately equal intervals from the bulk A and B prepared samples. These were used for homogeneity testing. Each participant received randomly drawn samples from the remaining A and B samples. A unique participation code was assigned to each sample set (combined A and B sample). 5.4 Packaging and Instructions Each sample was sealed in a plastic bag, labelled with the program name and whether sample A or B. Samples were packed into a sturdy box. Participants were instructed to test according to the nominated test method and report to the accuracy indicated on the ‘results log’ sheet. See ‘Appendix A’ for a copy of the instructions issued to participants and ‘Appendix B’ for the log sheet used. A set of instructions and log sheet were placed in the box prior to sealing and despatch. 5.5 Quarantine Samples sent to Western Australia (WA) are subject to quarantine regulations that require treatment of the soil prior to importation into WA. Samples sent to WA are heat treated and compliance certificates enclosed with samples. Where necessary additional information regarding handling and preparation of the sample may be included. 5.6 Sample Dispatch Samples were dispatched to participants in October 2017 using Toll Priority. Dispatched samples are tracked from despatch to delivery to each participant by LabSmart Services. 5.7 Homogeneity Testing Samples for homogeneity testing were packed in the same way as those for participants. Ten samples were selected at approximately equal intervals



throughout the set of samples. The same instructions were given to the laboratory performing the homogeneity testing. Results for the proportional calliper 2:1 test gave satisfactory results as shown in table 5.7A. There were a few samples were the prescribed 100 particles could not be attained on the 13.2 sieve. These are shown in bold. Further discussion regarding this aspect of the test can be found in section 3.3. Analysis of the homogeneity testing results indicated that the variability associated with the proficiency samples was satisfactory (Table 5.7A). The average value for each homogeneity test lies within 1 s.d of the participant’s median value. The assessment of the homogeneity provides confidence that any outliers identified in the program represent statistically valid outliers. 5.8 Participation Ninety-nine participants entered the program. The nominated date for participants to return their results was 9 November 2017. There were seven participants (7%) who were unable to return their results in time for inclusion in the final report. 5.9 Statistics Z-Scores were calculated for each test and used to assess the variability of each participant relative to the consensus median. A corresponding z-score graph was produced for each test. The use of median and quartiles reduces the effect that outliers have on the statistics and other influences. Therefore, z-scores provide a more realistic or robust method of assessment. Some results were reported by participants to more decimal places than requested as part of the proficiency program and by others to fewer decimal places. In all instances test results have been used as submitted by participants. Assessment of participant’s data is undertaken to ensure results are statistically comparable. Checks are undertaken to ensure the results calculated matches that reported by the participant and that the appropriate corrections etc. have been applied if required. The level of checking required varies from program to program. If significant inconsistencies are identified the results may be removed or amended with the discrepancy highlighted. A z-score is one way of measuring the degree of consensus with respect to the grouped test results. The z-scores in this report approximate standard deviations. For each test a z-score graph is shown. Use the graph to visually check statistically how you compare to other participants. The following bar (Figure 5.2) is shown at the bottom of each graph. This helps to quickly visualize where each participant’s result falls.



Sample A

Test Results Average Minimum Maximum Range s.d

Particle Size Distribution (% Passing) Units H1 H2 H3 H4 H5 H6 H7 H8 H9 H10

13.2 mm % 63.04 63.78 62.98 63.12 63.13 63.14 63.21 63.11 62.96 63.22 63.17 62.96 63.8 0.8 0.23

9.5 mm % 40.55 40.35 40.66 40.80 40.64 40.34 40.32 40.25 40.83 40.76 40.55 40.25 40.8 0.6 0.22

6.7 mm % 11.10 10.86 10.84 11.01 11.02 10.46 10.49 10.55 10.47 10.58 10.74 10.46 11.0 0.6 0.25

4.75 mm % 4.57 4.68 4.66 4.65 4.80 4.39 4.38 4.34 4.43 4.39 4.53 4.34 4.8 0.5 0.16

Material finer than 75 µm (By Washing) % 2.62 2.92 2.97 2.95 3.07 2.59 2.66 2.64 2.65 2.72 2.78 2.59 3.07 0.48 0.18

Flakiness index % 7.4 8.7 7.5 9.7 7.6 7.1 7.9 7.0 9.0 7.8 8.0 7.0 9.7 2.7 0.88

Average Least Dimension - 20.1 mm 7.4 7.7 7.7 7.6 7.8 7.8 7.6 7.7 8.0 7.8 7.7 7.4 8.0 0.6 0.16

Average Least Dimension - 20.3 mm 9.3 9.1 9.3 9.0 9.2 9.3 9.2 9.3 9.1 9.2 9.2 9.0 9.3 0.3 0.09

Sample B

Test Results Average Minimum Maximum Range s.d

Units H1 H2 H3 H4 H5 H6 H7 H8 H9 H10

Apparent particle density t/m3 2.846 2.833 2.839 2.840 2.847 2.840 2.846 2.837 2.831 2.834 2.839 2.831 2.847 0.016 0.006

Particle density - dry basis t/m3 2.673 2.657 2.676 2.673 2.680 2.666 2.671 2.659 2.655 2.664 2.667 2.655 2.680 0.025 0.009

Particle density - saturated-surface dry t/m3 2.734 2.719 2.734 2.732 2.738 2.727 2.732 2.722 2.717 2.724 2.728 2.717 2.738 0.021 0.007

Water Absorption % 2.270 2.321 2.133 2.196 2.187 2.281 2.287 2.346 2.325 2.256 2.260 2.133 2.346 0.213 0.068

Proportional Calliper 2:1 % 20.4 22.5 22.0 18.2 23.3 20.1 21.8 19.1 20.9 - 20.9 18.2 23.3 5.1 1.6

Table 5.7A Homogeneity results for sample A & B



Review Weak

Consensus Strong Consensus

Weak Consensus

Review

Figure 5.2 Z-score interpretation bar

For example:

• A strong consensus (i.e. agreement) means that your test result is close i.e. within 1 standard deviation of the median.

• A weak consensus means that your test result is satisfactory and is within 2 standard deviations of the median.

• If you have obtained a test result that is outside 2 standard deviations, then it

may be worth reviewing your testing processes to ensure that all aspects are satisfactory. Only those obtaining a z-score approaching 3 (I.e. outside 2.75 range) have been highlighted in the report for review.

If you have obtained a test result that is outside 3 standard deviations, then you will need to investigate your testing processes to ensure that all aspects are satisfactory. Participant assessment is not based purely on statistical analysis. Compliance to proficiency program requirements including the correct calculation of results and adherence to program requirements may also be used as part of the assessment process. Participants may also be asked to investigate any discrepancies detected with the paperwork submitted. For further details on the statistics used in this proficiency program can be obtained from LabSmart Services or download the ‘Participant Guide’ from the LabSmart Services website. 5.9.1 Z-score summary

A “Z-Scores Summary” is issued soon after most results are received. It gives participants early feedback as to any program outliers. The summary is usually available on the LabSmart Services website up until the final report is issued. The final report supersedes the z-score summary. The final report contains detailed technical feedback regarding the performance of tests and revised z-scores. The inclusion of late results or corrections are at the discretion of the program coordinator. In some instances, this may change some of the z-scores slightly but generally the performance outcome remains the same. If there is any impact it will be discussed within section 5.1 of the report. 5.9.2 Comparing statistics from one program to another

The statistics generated from one proficiency program are not usually comparable to those from another proficiency testing program. Only very general comparisons may be possible. The reason statistics from one program



may not be compared to another is due to the range of variables that differ from one proficiency program to another. These variables include:

• Type of material selected

• The number of participants

• Experience of participants

• Test methodology variations

• Equipment used

• Test methods used

• Experience of supervisors

• Range of organisations involved

• Program design and the statistics employed The program outcome represents a ‘snap shot’ of the competency within the industry and hence provides an overview of the industry. The more participants involved in the program then the more representative the overview. 5.9.3 Measurement uncertainty

The statistics detailed in this program do not replace the need for laboratories to separately calculated measurement uncertainties (MU) associated with each test when required by the client or NATA. The proficiency program does give information useful for calculating the MU and bench marking the MU calculated. 5.9.4 Metrological traceability

The assigned median value used in this proficiency testing program is derived from participant performance and is not metrologically traceable. 5.10 Non-statistical Outliers One of the issues faced by proficiency testing providers is what to do with an incorrect result even if its z-score is satisfactory. In many cases they cannot be detected but still can have a significant impact on the statistics calculated. This can cause biased (or unfair) outcomes for other participants. To limit the effect that erroneous results may have on a program additional information is requested to allow the main results to be recalculated. In some cases, results shown to be erroneous may be reject for inclusion in the program. If the result does not add any statistical bias it is left in the program. The result however is incorrect even though it may have a satisfactory z-score. To highlight that the participant needs to investigate erroneous results it is considered a ‘non-statistical outlier’. This may also be applied to non-compliance to program requirements e.g. incorrect reporting of results etc or incorrect partial calculations/data. Non-statistical outliers were not used as part of the assessment process for this program.



75 Appendix A -Instructions.docx Page 1 of 2

LabSmart Services Helping laboratories to work smarter!

Proficiency Testing Program

Aggregates – 2017 (75)

INSTRUCTIONS FOR TESTER

1. Please check that the package you have received contains:

• Results log sheet.

• Plastic sample bag marked Sample A – approximately 1.5 kg

• Plastic sample bag marked Sample B – approximately 3 kg Contact LabSmart Services (0432 767 706) if material has escaped from the bags or any item is missing. Please do not mix sample A and B as they are different aggregate samples.

2. Read all the instructions and examine the results log sheet prior to testing. Follow

these instructions carefully during testing.

3. Use AS 1141 test methods unless you are unable to do so. Complete those tests that you are able to perform. You may perform a test even if you are not NATA accredited for the test.

4. Sample A (1.5 kg)

❖ Use all of Sample A. It has been specially prepared for this proficiency program to ensure consistency and is smaller than normally expected for this size aggregate.

❖ Oven dry and wash the sample to perform the “Material finer than 75 micron” test. Oven dry and perform the PSD test.

❖ Record the diameter of the sieve set used and the method of drying.

❖ Do not lose any of the sample from the PSD test. Keep the fractions obtained separated.

❖ From the PSD test use the information gained and the fractions to perform

the Flakiness Index determination. Save the material tested.

❖ Do not lose any of the sample. ❖ Next perform the ALD using the saved material.

❖ Circle on the results log whether a slotted gauge or vernier calliper etc was

used for the average least dimensions test.

Appendix A



75 Appendix A -Instructions.docx Page 2 of 2

5. Sample B (3 kg) ❖ Perform the density and absorption tests on sample B.

❖ Wash the sample to remove loose particles and dust coatings.

❖ Do not lose any of the 3 kg sample.

❖ Save the sample and oven dry.

❖ Perform the ‘Particle shape by proportional calliper’ test using this material. 6. Record all information and calculations as per the proficiency testing results log sheet

and to the accuracy shown on the results log sheet. In many cases a greater reporting accuracy is required compared to that nominated by the test method standard.

7. The Laboratory Manger or person responsible for checking should sign the log

sheet to indicate that it has been checked. 8. If more than one technician is involved in the testing then please ensure that the

laboratory’s records indicate which technician did each test.

9. It is recommended that the entire sample following testing be retained until the

proficiency testing technical report for this program has been issued.

10. Have a query? Contact Peter Young at LabSmart Services. Phone 0432 767 706.

11. Please fax or e-mail the “Results Log” to LabSmart Services by 9 Nov 2017

Fax: (03) 8888 4987 OR E-mail: [email protected]

12. Please retain the completed “Results Log” as this contains your participation code that will identify your results in the technical report covering the proficiency testing program. It is also recommended that a copy of completed worksheets be kept with the results log in your proficiency file.

13. Proficiency testing can also form part of a laboratories training records for the

technician who performed the test.

Thank you for participating in this proficiency testing program.



Aggregates PT Results log – 2017(75) V4 Copyright: LabSmart Services Pty Ltd Page 1 of 2

LabSmart Services Helping laboratories to work smarter!

Aggregates Proficiency Testing Program – 2017 (75)

RESULTS LOG Participation Code: XX Laboratory:

Please fax (03) 8888 4987 or e-mail ([email protected]) the completed results log by

9 November 2017

Date proficiency sample received:

Condition of samples: A B

Sample A - Tests Report to: Result Method

AS 1141 Tick or enter method used

Particle Size Distribution, Initial Dry Mass (g)

Nearest 0.1*

11.1

Dry mass after washing (washed mass, g)

Mass

Retained (per sieve, g)

% Passing

19.0 mm

13.2 mm

9.5 mm

6.7 mm

4.75 mm

Pan

Diameter of sieves used (mm)

Materials finer than 75 μm (by washing) Nearest 0.01 % * 11.1,12

Method of drying

Flakiness index (FI) Nearest 0.1 %

15 Mass of sample used Nearest 1 g

Method of drying

Average least dimension (ALD)

Slotted Gauge OR

Nearest 0.1 mm

20.1 Flatbed Tray Gauge OR

Vernier Calliper/ Dial Gauge

*Only if balance has appropriate accuracy

Appendix B



mailto:[email protected]

Aggregates PT Results log – 2017(75) V4 Copyright: LabSmart Services Pty Ltd Page 2 of 2

Aggregates Proficiency Testing Program – 2017 (75)

Sample B - Tests Report to: Result Method

AS 1141 Tick or enter method used

Apparent particle density Nearest 0.01 t/m3

6.1

Particle density on a dry basis Nearest 0.01 t/m3

Particle density on a saturated-surface-dry basis

Nearest 0.01 t/m3

Water absorption Nearest 0.01 %

Particle shape by proportional calliper (2:1) Nearest 0.1 %

14

Particle shape by proportional calliper (3:1) Nearest 0.1 %

Tested by:

*Only if balance has appropriate accuracy

COMMENTS:…………………………………………..............………………………

...................…………………………………………..............………………………

...................…………………………………………..............………………………

------------------------------------ ---------------------------------- --------------- Supervisor Name (Please Print) Signature Date

In signing the above, I acknowledge that the above results have been approved and have been checked. I will also ensure that the results are kept confidential both internal and external to the laboratory until the issue of the final technical report covering this proficiency program.

Thank you for participating. Please retain these sheets for your records.

________________________________________________________________________

Have a query? Contact Peter at LabSmart Services. Phone: 0432 767 706.



1 P4 37.4 0.27 22.6 0.21 29.7 -0.02 5.6 -0.13

2 A2 35.2 -3.01 # 22.6 0.26 31.4 2.45 6.0 0.69

3 D5 37.4 0.23 22.8 0.44 29.7 0.02 5.6 -0.22

4 L6 37.3 0.09 21.4 -1.25 29.6 -0.05 5.6 -0.25

5 K9 37.5 0.46 22.4 0.03 30.8 1.62 5.0 -1.66

6 M5 39.1 2.83 21.3 -1.35 28.7 -1.35 5.8 0.18

7 P8 37.3 0.17 22.0 -0.42 30.4 1.06 5.5 -0.41

8 C3

9 N9 36.6 -0.96 23.7 1.58 28.2 -2.09 6.2 1.19

10 T2 37.7 0.76 21.2 -1.47 30.4 1.00 5.9 0.66

11 X6 37.3 0.12 22.2 -0.30 30.2 0.81 5.7 0.07

12 G7 36.2 -1.51 20.9 -1.82 32.6 4.20 # 5.8 0.24

13 A4

14 Q3 37.3 0.19 22.3 -0.13 30.4 1.10 5.4 -0.83

15 R5 35.1 -3.25 # 24.2 2.19 30.0 0.51 5.9 0.49

16 W6 37.5 0.46 22.3 -0.06 30.2 0.78 4.9 -1.92

17 S2 37.3 0.06 15.9 -7.89 # 29.5 -0.30 5.8 0.36

18 B9 38.4 1.71 22.5 0.10 28.9 -1.18 5.7 -0.02

19 U3

20 P5 37.1 -0.16 21.9 -0.55 30.1 0.61 5.1 -1.65

21 G8 37.4 0.24 22.3 -0.07 30.3 0.87 5.4 -0.66

22 C2 37.2 -0.04 20.7 -2.01 30.7 1.44 6.4 1.70

23 F4 35.4 -2.74 23.0 0.68 30.1 0.67 6.2 1.28

24 M8

25 E3 23.2 -21.1 # 23.6 1.44 29.4 -0.40 5.0 -1.77

26 R4 36.8 -0.61 23.1 0.83 30.0 0.49 5.6 -0.26

27 N8 38.7 2.21 21.5 -1.03 29.2 -0.72 5.9 0.58

28 M2 38.4 1.84 22.9 0.64 28.8 -1.23 5.5 -0.59

29 B8 39.6 3.60 # 19.9 -3.07 # 30.5 1.12 5.8 0.41

30 J5 36.2 -1.54 22.1 -0.35 30.3 0.83 4.9 -2.16

31 K6 37.1 -0.15 23.1 0.85 29.5 -0.29 5.4 -0.86

32 F5 37.7 0.73 22.3 -0.16 30.6 1.33 5.2 -1.27

33 Q4 36.3 -1.33 21.3 -1.37 30.4 1.08 5.5 -0.53

34 R9 38.8 2.30 21.5 -1.12 29.6 -0.13 5.7 0.11

35 Y4 35.0 -3.28 # 21.8 -0.74 29.4 -0.37 5.9 0.58

36 G3 35.5 -2.56 22.9 0.58 29.5 -0.22 5.6 -0.11

37 W8 38.3 1.69 23.2 1.03 28.3 -2.01 5.1 -1.40

38 X2 37.5 0.42 24.7 2.85 27.1 -3.68 # 5.6 -0.31

39 L8 36.1 -1.67 22.5 0.18 29.6 -0.12 5.9 0.59

40 D7 37.7 0.73 21.0 -1.67 28.8 -1.20 4.7 -2.57

41 B5 36.2 -1.51 23.9 1.85 29.4 -0.39 6.0 0.80

42 V8 37.9 1.03 22.5 0.09 29.9 0.36 5.3 -1.04

43 J2 35.8 -2.20 25.1 3.26 # 29.4 -0.44 5.8 0.32

44 Y3

45 N7 37.3 0.07 23.1 0.88 29.1 -0.82 6.0 0.73

46 T4 37.7 0.68 22.3 -0.07 34.6 7.08 # 0.1 -14.4 #

47 Z3 36.1 -1.75 23.0 0.70 29.2 -0.72 56.9 132 #

48 Q7 38.0 1.25 20.7 -2.08 30.7 1.50 5.9 0.49

49 Y6 39.0 2.71 22.8 0.55 29.9 0.36 5.4 -0.64

50 C5 23.9 -20.0 # 22.1 -0.33 30.4 1.04 44.9 101 #

Appendix C - % Retained

Code

13.2 mm 9.5 mm 6.7 mm 4.75 mm

%

RetainedZ Score

%

RetainedZ Score

%

RetainedZ Score

%

RetainedZ Score



51 V9 37.2 0.01 22.3 -0.17 30.0 0.52 5.8 0.28

52 D4 38.1 1.32 22.9 0.66 29.5 -0.25 4.7 -2.55

53 Q5 37.3 0.13 23.8 1.68 30.1 0.62 5.0 -1.68

54 L9 37.1 -0.16 22.4 -0.03 28.8 -1.21 6.6 2.24

55 Y5 37.2 -0.09 22.5 0.07 28.2 -2.13 7.0 3.45 #

56 J7 37.5 0.50 22.5 0.16 30.6 1.27 5.2 -1.30

57 A8 37.1 -0.13 23.7 1.58 29.0 -0.93 5.3 -1.10

58 E6 36.0 -1.76 22.3 -0.09 28.6 -1.55 5.9 0.46

59 X8 37.2 -0.01 21.7 -0.80 29.9 0.28 5.8 0.23

60 U9 36.9 -0.42 21.5 -1.06 30.1 0.55 6.4 1.79

61 J8 36.9 -0.49 22.2 -0.29 29.9 0.33 5.5 -0.51

62 L3

63 A9

64 S8 36.8 -0.60 22.5 0.11 29.6 -0.17 6.2 1.34

65 P3 37.2 0.02 21.9 -0.62 29.3 -0.51 5.8 0.23

66 D6 36.7 -0.77 24.2 2.14 28.1 -2.31 6.1 1.00

67 K7 37.8 0.92 21.6 -0.99 29.6 -0.08 5.9 0.41

68 G9 37.1 -0.25 21.7 -0.88 30.0 0.53 5.8 0.36

69 F8 36.0 -1.82 22.7 0.33 29.9 0.35 5.7 0.02

70 Q2 36.7 -0.79 22.7 0.37 30.2 0.75 5.9 0.49

71 E5 37.2 -0.04 22.2 -0.24 30.4 1.06 5.4 -0.65

72 B7 36.7 -0.82 23.1 0.88 29.6 -0.12 5.7 0.10

73 N2

74 W7 38.3 1.67 22.7 0.36 29.1 -0.80 5.2 -1.22

75 Y8 38.3 1.56 22.5 0.18 29.2 -0.75 5.3 -0.88

76 G6 2.4 -52.3 # 1.5 -25.3 # 2.0 -39.6 # 0.4 -13.6 #

77 T9 36.7 -0.76 22.3 -0.15 30.6 1.26 5.9 0.49

78 R2 35.9 -2.04 21.9 -0.61 30.0 0.43 5.7 0.09

79 E4 38.9 2.49 23.3 1.10 29.8 0.13 5.3 -1.02

80 L7 36.8 -0.64 22.2 -0.24 30.0 0.51 5.5 -0.37

81 P6

82 K3 36.3 -1.45 23.1 0.87 27.7 -2.78 4.9 -2.05

83 D8

84 S3 37.8 0.89 20.7 -2.09 31.7 2.94 5.1 -1.63

85 M6 38.3 1.69 21.6 -0.97 30.1 0.59 5.7 -0.04

86 P7 36.8 -0.65 23.4 1.22 29.1 -0.87 6.4 1.84

87 K5 36.2 -1.56 22.5 0.15 30.5 1.20 6.2 1.31

88 R6 38.1 1.34 21.1 -1.59 31.1 2.06 5.2 -1.18

89 T8 39.2 2.94 23.4 1.26 28.4 -1.84 4.7 -2.55

90 X4 39.4 3.29 # 21.9 -0.60 28.6 -1.54 5.3 -1.09

91 B6 41.1 5.89 # 19.8 -3.19 # 29.4 -0.42 5.1 -1.39

92 F7 38.4 1.84 22.0 -0.53 29.3 -0.51 5.8 0.39

93 E9 37.0 -0.36 22.5 0.07 29.8 0.23 5.7 -0.09

94 L4 39.0 2.75 21.1 -1.52 29.6 -0.10 5.3 -1.04

95 M4 37.1 -0.16 21.4 -1.25 31.4 2.51 5.3 -0.91

96 E7

97 S6 40.0 4.23 # 20.5 -2.33 30.4 0.98 4.7 -2.67

98 X7 36.2 -1.49 22.1 -0.32 30.1 0.54 4.9 -2.01

99 K2

Appendix C - % Retained (Continued)

Code

13.2 mm 9.5 mm 6.7 mm 4.75 mm

%

RetainedZ Score

%

RetainedZ Score

%

RetainedZ Score

%

RetainedZ Score



Statistic

Number of results 60 60 60 60

Median 37.2 22.4 29.7 5.7

First Quartile 36.7 21.8 29.3 5.4

Third Quartile 37.6 22.9 30.2 5.9

IQR 0.9 1.1 0.9 0.5

Normalised IQR 0.7 0.8 0.7 0.4

CV (%) 1.8 3.7 2.4 6.8

Minimum 35.0 20.7 28.1 4.7

Maximum 39.1 24.7 31.4 6.6

Range 4.1 4.1 3.3 1.9

Note: "% retained" results have been calculated by the program coordinator based on submitted mass retined results.

A # indicates where the z-score calculated is either greater then 3 or less than -3. Values above 3 are not outliers

and do not need to be investigated but help identify sieves that have amounts retained that differ significantly

from others in the program. This assists those with outliers from the "% Passing" to identify sieves that may have

contributed to the outlier. Codes for all participates are shown. Codes shown in orange denote participants that did not

supply sufficient data for the '% Retained ' to be calculated. The results column shows a blank entry for those

participants that did not submit a result for this test. Minimum, Maximum and Range are calculated with values

greater than 3 or -3 excluded.

13.2 mm 9.5 mm 6.7 mm 4.75 mm



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