This article was downloaded by: [Bangor University]On: 19 December 2014, At: 20:51Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registeredoffice: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK

ErgonomicsPublication details, including instructions for authors andsubscription information:http://www.tandfonline.com/loi/terg20

Investigating slips, trips and falls in theNew Zealand dairy farming sectorTim Bentley a , David Tappin b , Dave Moore b , Stephen Legg c ,Liz Ashby d & Richard Parker da Department of Management and International Business , MasseyUniversity at Albany , Auckland, New Zealandb Forest Research , Centre for Human Factors and Ergonomics ,Auckland, New Zealandc Centre for Ergonomics and Occupational Safety and Health ,Massey University , Palmerston North, New Zealandd Forest Research , Centre for Human Factors and Ergonomics ,Rotorua, New ZealandE-mail:Published online: 20 Feb 2007.

To cite this article: Tim Bentley , David Tappin , Dave Moore , Stephen Legg , Liz Ashby &Richard Parker (2005) Investigating slips, trips and falls in the New Zealand dairy farming sector,Ergonomics, 48:8, 1008-1019, DOI: 10.1080/00140130500182072

To link to this article: http://dx.doi.org/10.1080/00140130500182072

PLEASE SCROLL DOWN FOR ARTICLE

Taylor & Francis makes every effort to ensure the accuracy of all the information (the“Content”) contained in the publications on our platform. However, Taylor & Francis,our agents, and our licensors make no representations or warranties whatsoever as tothe accuracy, completeness, or suitability for any purpose of the Content. Any opinionsand views expressed in this publication are the opinions and views of the authors,and are not the views of or endorsed by Taylor & Francis. The accuracy of the Contentshould not be relied upon and should be independently verified with primary sourcesof information. Taylor and Francis shall not be liable for any losses, actions, claims,proceedings, demands, costs, expenses, damages, and other liabilities whatsoeveror howsoever caused arising directly or indirectly in connection with, in relation to orarising out of the use of the Content.

This article may be used for research, teaching, and private study purposes. Anysubstantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,systematic supply, or distribution in any form to anyone is expressly forbidden. Terms &

Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

Investigating slips, trips and falls in the NewZealand dairy farming sector

TIM BENTLEY{*, DAVID TAPPIN{, DAVE MOORE{,STEPHEN LEGG§, LIZ ASHBY} and RICHARD PARKER}

{Department of Management and International Business, Massey University at Albany,

Auckland, New Zealand

{Centre for Human Factors and Ergonomics, Forest Research, Auckland, New Zealand

§Centre for Ergonomics and Occupational Safety and Health, Massey University,

Palmerston North, New Zealand

}Centre for Human Factors and Ergonomics, Forest Research, Rotorua, New Zealand

The paper presents findings from 39 detailed follow-up investigations of slips,

trips and falls (STF) incurred by individuals working in New Zealand’s dairy

farming industry. The study sought to identify the key contributory risk

factors for STF in this sector to provide evidence to support intervention

design, and to determine the effectiveness of the investigative methodology

used to achieve these objectives. Findings from the follow-up investigations

included an analysis of factors related to the underfoot surface, underfoot

hazard and footwear. Of note here was the propensity for STF-involved

workers to not see or identify an underfoot hazard due to concurrent visual

task distractions, and for workers to use footwear that both lacked effective

tread and was unsuitable for the task and underfoot surface. Key latent risk

factors and their interactions identified included problems associated with

time pressure and related time-saving behaviours and the presence of design

errors that, for example, required workers to climb onto equipment to view

aspects of the task they were working on. The paper concludes that the

potential resource and logistical problems associated with conducting

detailed STF investigations are outweighed by the opportunity to collect

rich data on key risk factors and their interactions in STF research.

Keywords: Occupational injury; Slips, trips and falls; Injury investigations;

Dairy farming

1. Introduction

Slips, trips and falls (STF) are a leading cause of occupational morbidity and mortality in

New Zealand (Accident Compensation Corporation 1999) and elsewhere (e.g. National

*Corresponding author. Email: T.A.Bentley@massey.ac.nz

Ergonomics, Vol. 48, No. 8, 22 June 2005, 1008 – 1019

ErgonomicsISSN 0014-0139 print/ISSN 1366-5847 online ª 2005 Taylor & Francis Group Ltd

http://www.tandf.co.uk/journalsDOI: 10.1080/00140130500182072

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

Occupational Health and Safety Commission 1998, Cotnam et al. 2000, National Institute

for Occupational Safety and Health 2000). The New Zealand dairy farming industry has

particularly high numbers of STF injury and compensation claims compared to other

major New Zealand industry sectors (Accident Compensation Corporation 1999,

Occupational Safety and Health 2001). Dairy farming has received little attention in the

international ergonomics literature, with most published studies in this sector concerned

with issues such as musculoskeletal problems during milking and farm vehicle safety.

Despite the known prevalence of STF in this industry sector, no published New Zealand

research focusing on the problem of STF in dairy farming was identified from a search of

the literature. Indeed, most published occupational injury research in New Zealand,

outside of forestry, which is well served by a dedicated strategic ergonomics research

programme (Parker et al. 2002), has been limited to descriptive injury epidemiology

studies, including analyses of coroners’ records, national compensation claims data,

hospitalization data and company injury data. However, few injury prevention researchers

would disagree that the development of effective interventions to reduce the level of

occupational STF risk is greatly enhanced where researchers are able to determine the role

of key risk factors and their interactions in occupational STF, and the ‘upstream’

organizational and cultural contexts within which high-STF risk tasks take place (Shaw

and Blewett 1998, Bentley and Haslam 2005). Indeed, the identification of these factors is

fundamental to a systems approach to injury prevention, and yet the difficulties associated

with undertaking detailed incident investigations of STF have meant that many

researchers (these authors included) have tended to rely on secondary sources of injury

data in the analysis of multiple occupational STF events (see Bentley and Haslam 2005 for

a discussion of epidemiological approaches to the investigation of occupational falls).

Within the ergonomics research community there is a growing emphasis on

understanding STF from a systems perspective, as the published literature in this area

has grown apace during the last decade or so, moving beyond the micro focus of footwear

and slip resistance concerns to studies and reviews that recognize the multi-causal nature

of these complex events. This escalation of research interest reflects a growing awareness

of the extent of the occupational STF problem across many industry sectors

internationally, and the realization that such incidents are generally preventable, rather

than inevitable ‘everyday accidents’, particularly where intervention measures can be

based on a detailed understanding of the factors that are contributory to STF risk (e.g.

Leamon and Murphy 1995, Bentley and Haslam 2001, David and Ridd 2001).

The present study was a direct consequence of recognition at national level that STF

were a leading cause of injury and compensation cost in the dairy farming sector. Three

national bodies, the Health Research Council of New Zealand, the Accident

Compensation Corporation (ACC) and the Occupational Safety and Health division of

the Department of Labour, jointly funded a major collaborative programme of research

focusing on STF injuries in dairy farming and small business residential construction

sectors (this paper reports on findings from the dairy farming research only). The

research programme has three major research phases: an exploratory phase – to

determine key areas of risk within the sector for detailed research attention in the analysis

phase (see Bentley and Tappin 2004 for exploratory phase findings); an analysis phase –

detailed analysis of STF incidents and tasks identified as key areas of concern in phase 1,

together with semi-structured interviews generating additional general STF information

unrelated to the specific event under investigation; and an intervention phase – design of

measures targeting the control of risk factors identified in the analysis phase. This paper

focuses on methods and findings from the analysis phase.

Slips, trips and falls 1009

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

The aims of the research were to identify and analyse key individual, equipment, task,

environment, design and work organization factors and their interactions in STF injury

risk, and to better understand the organizational, psychosocial and environmental

contexts within which high-STF risk tasks take place, for the purpose of designing

research-based interventions. The study also aimed to examine the effectiveness of this

investigation methodology to achieve the above aims.

2. Method

Thirty-nine dairy farming STF incident follow-up investigations were conducted. The

sample was selected on the basis of the STF-involved worker making a claim to ACC for

compensation during the 12-month period of the analysis: July 2002 to June 2003. To

protect the privacy of claimants, ACC sent a standard letter of invitation to all STF-

involved claimants to participate in the study. Claimants were then asked to contact the

researchers directly if they were willing to participate. Participants signed a consent form,

noting that they would not be identified individually in any publications arising from the

research, and received a one-page information sheet about the study.

Each follow-up investigation involved a detailed face-to-face semi-structured interview

with the injured person, along with injury site observations, footwear analysis and

collection of video and photographic evidence. The investigation schedule was adapted

from that used by Haslam and Bentley (1999) for follow-up investigations for STF

involving postal delivery employees. In preparation of the study methods, a series of semi-

structured site interviews and visits to dairy farms provided information that assisted the

production of industry-relevant questions, and the investigation schedule was piloted with

local people working in the industry. The investigation schedule had four main sections.

The first collected information about the worksite and establishment and the individual

claimant. The second was the Events and Contributory Factors Chart (Haslam and

Bentley 1999) (see figure 1 for an example of a dairy farming STF case chart), detailing

events from ‘activity immediately preceding the STF’ to ‘post injury event’ and

contributory risk factors at the appropriate point in the incident sequence of events.

The third section contained a large number of detailed questions about the incident

and addressed a range of individual, equipment, task and organizational risk factor areas.

The fourth and final section questioned the respondent on their perceptions of risk and

various other incident-independent issues, providing further contextual and ‘upstream’

information to assist the researchers in understanding the interrelationship between

factors underlying the STF event. Where appropriate, information received in response to

the detailed questions was used to construct the Events and Contributory Factors Chart.

Site visits and interviews took, on average, around 90 min to complete, and wherever

possible were conducted at the precise location at which the injury occurred. The data

produced from these methods were analysed by the investigators to create a detailed

picture for each incident.

3. Results and discussion

3.1. Demographic and geographic distribution of claimants

A sample of 39 respondents was included in the study. While the logistical demands of the

study restricted the size of the sample, the demographic, temporal and geographical

distributions for cases investigated were sufficiently similar to those found in the

1010 T. Bentley et al.

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

epidemiological analysis of ACC claims data for the 2-year period 2000 – 2002 (Bentley

and Tappin 2004) (undertaken in Phase 1) to suggest a reasonably representative sample

of all STF injury events resulting in compensation claims to ACC. Table 1 summarizes

the demographic distribution of the sample, making comparison with the wider

population of STF claimants based on the analysis of ACC claims for the period

2000 – 2002 for age and gender distributions.

While the distribution of claimants’ gender is representative of the wider population of

STF claimants, this is not the case for age, where the youngest workers were under-

represented in the study. In explanation, it is possible that younger employees would be

less likely to be farm owners or managers and, consequently, less at liberty to respond to

the study. The distribution for time worked in dairy farming shows the majority of

respondents were very experienced in this industry. Furthermore, many respondents had

considerable experience on the farm at which the STF took place, with 56% of

respondents having worked on the farm for over 10 years.

Much of New Zealand’s dairy farming sector is concentrated in the central part of the

North Island, particularly the Waikato region. The high proportion of investigations in

this region (46%) reflects the wider population of claimants for this sector (36%), as

identified from 2000 – 2002 ACC claims data. The distribution of investigations across the

other major regions also represents a successful sample in terms of regional

representativeness, with the remainder of investigations undertaken in the Taranaki,

Canterbury, Northland and Bay of Plenty regions.

3.2. Incident location and task at the time of slips, trips and falls

Table 2 shows the distribution of STF site location and tasks commonly undertaken at

time of dairy farming STF for major locations.

Figure 1. Example of Contributory Factors and Events Chart for dairy farming slip, trip

and fall (STF) case investigated.

Slips, trips and falls 1011

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

STF occurred in each location in similar proportions to those identified from the

analysis of ACC claims, with paddock, cowshed and yard being the major locations.

Table 2 indicates that STF occurred in a range of different locations, with paddock and

cowshed the most common. Tasks being undertaken at the time of the STF involved

some form of interaction with cattle in 20 (51%) cases.

3.3. Underfoot surface and hazard identification and control

Table 3 shows the distribution of underfoot surface and hazards identified for each

underfoot surface category for dairy farming STF investigated. Concrete surfaces, found

predominantly in the cowshed and yard, appear to be almost permanently slippery due to

the presence of water, milk, manure or other contaminants, such as alkaline for cleaning.

The variety of surfaces on which dairy farmers work indicates they may require a range of

different footwear. For example, four slips occurred on steel surfaces, while others

occurred on grass or mud (nine), wood (five) and concrete surfaces (12).

The analysis considered the hazard and incident events from the view of an

information processing model of hazard detection and control (Ramsey 1985, Kines

2003). This allowed analysis of information processing in relation to hazard detection

from the view of whether the injured worker had perceived the hazard, identified it as a

risk and attempted to avoid or control the hazard. In 65% of cases the underfoot hazard

was not detected or identified as a STF hazard by the worker prior to or at the time of the

STF. A range of explanations was provided by respondents for their failure to detect the

hazard (table 4).

Clearly, concurrent visual tasks, notably watching the stock (undertaken at the same

time as walking and negotiating the underfoot surface) are a major risk area for STF on

Table 1. Demographic distribution of dairy farming slips, trips and falls (STF) claimantsinvestigated

Variable

Dairy farming cases

(n) (%)

ACC STF claimants

2000 – 2002 (%)

Age group (years)

15 – 40 3 8 49

41 – 50 19 48 22

51 – 60 13 32 22

4 60 5 12 7

Gender

Female 10 25 28

Male 23 75 72

Time in dairy farming (years)

0 – 5 2 5

6 – 10 9 22

11 – 20 3 8

21 – 30 15 37

4 30 11 28

Employment status

Farm owner 21 52

Sharemilker 13 32

Employee 6 16

ACC=Accident Compensation Corporation.

1012 T. Bentley et al.

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

Table 2. Distribution of slips, trips and falls (STF) incident location and tasks commonlyundertaken at time of STF in major locations

Location

(general) n % Location (specific) n %

Tasks common in location at the

time of the STF

Paddock 1 3 Farm vehicle 3 8 Getting cows into race

4 5 Near shed or race 4 10 Getting cows in/out for milking

By gate or fence 2 5 Herding cows generally

Grass bank/slope 2 5 Fence moving/maintenance

Other 3 8 Feeding out

Maintenance activities

Cowshed/

milking shed

11 28 Pit 4 10 Milking

Steps 3 8 Preparation for milking

Milk vat 2 5 Cleaning

Other 2 5 Maintenance

Yard 4 10 Cleaning

Inspection/maintenance

activities

Race 4 10 Getting cows in/herding cows

Calving

Other 6 17 Ladder/plank 2 5 Maintenance activities

including building repair and

painting

Cleaning activities

Loading/dumping

Table 3. Distribution of underfoot surface and hazards for dairy farming slips, trips and fallsinvestigated.

Underfoot surface n % Common underfoot hazards for underfoot surface

Concrete 12 30 Water/water and manure contaminant

Water and alkaline contaminant

Obstacle underfoot

Irregular steps

Dry/uncontaminated surface

Grass/grass and mud 9 22 Wet/dewy grass or mud

Slippery object on grass (e.g. log or branch)

Hole

Rutted or uneven surface

Dry ground

Farm vehicle 5 12 Protruding pedal/gear lever (in dismount area)

Wet/muddy footplate

Wet trailer surface

Wet/muddy wheel hub

Steel surface (non-vehicle) 4 10 Wet steps

Wet ramp

Obstacle on walking surface

(that should not be present)

5 13 Hose

Barbed wire

Steel rods

Wood 5 13 Log

Ladder

Plank

Slips, trips and falls 1013

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

dairy farms (this factor is discussed further in Section 3.6). The underfoot hazard

involved in the STF should have been where it was, in the judgement of the injured

worker, in 25 cases (64%). In these cases the hazard was usually a permanently slippery

surface or some physical feature of the working environment, such as steps or a slope or

building materials. Underfoot hazards were perceived to be where they were erroneously

in 12 cases (31%), sometimes as a result of the actions or inactions of a third party (e.g.

another worker or visitor). The hazard was noted by respondents as being present on this

and other farms ‘always’ or ‘usually’ in 24 cases (62%).

3.4. Fall initiating event

The largest fall initiating event category for dairy farming STF cases investigated was

foot slips (60%), reflecting the predominance of this mechanism of injury for STF in

industrial situations where tasks are carried out in wet, varied and relatively uncontrolled

environments (e.g. Bentley and Haslam 2001). Foot slips involved a range of underfoot

surfaces and underfoot hazards, although the major surface type was concrete (in the

cowshed and yard), comprising 30% of all cases investigated. The contaminants that

make concrete surfaces slippery varied, but often involved water, which is used

extensively for cleaning in and around the milking shed. Other underfoot contaminants

involved in foot slips included cow manure, milk, mud and alkaline cleaner. All these

contaminants are commonly found in and around the cowshed, while mud and manure

are also commonly present in paddocks, forming build-up on footwear and underfoot

surfaces such as steps and rails. The injured worker’s foot tripped or caught on some

object in 21% of cases. Obstacles included hosepipes around the cowshed and yard, steel

rods, barbed wire and irregular steps.

3.5. Footwear

Footwear condition, particularly the relief of the sole and wear status in relation to the

underfoot surface worked on, is known to be an important factor in slipping injuries

(Tisserand 1985, Haslam and Bentley 1999). This is particularly true where work takes

place with water, oil and other forms of contaminant affecting underfoot conditions (e.g.

Gronqvist 1999, Manning and Jones 2001). In all but five dairy farming cases the injured

worker was wearing gumboots at the time of the STF. Overall, footwear worn at the time

of the STF was more than 6 months old in 73% of cases and 1 year or older in 45% of

cases. Footwear was inspected and photographed by the researchers in 30 dairy farming

cases. Of these 13 (43%) had ‘poor’ or ‘very poor’ condition tread (worn smooth or little

tread remaining or damaged tread). This is of concern given the poor underfoot

Table 4. Reasons given for not detecting, perceiving or identifying underfoot hazard

Why underfoot hazard undetected n %

Was looking at something else (concurrent visual task) 18 45

Something that obscured view of underfoot hazard (e.g. object being carried) 5 13

Insufficient illumination/weather conditions 1 2

Hazard seen, but not assessed as STF hazard 2 5

Total 26 65

STF=slip, trip and fall.

1014 T. Bentley et al.

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

conditions faced by workers in this sector and the high rate of STF injuries recorded. The

footwear worn at the time of the STF was the footwear normally worn in that area of the

farm and for that task in 88% of cases. Some 83% of respondents reported wearing the

same footwear on all parts of the farm and for all tasks. This fact belies the reality of the

many and varied underfoot surfaces present on a typical dairy farm and the wide variety

of tasks performed by these workers (see table 3).

3.6. Key risk factors and common risk factor interactions

Table 5 shows key risk factors identified from detailed investigations to be contributory

to dairy farming STF injuries.

A major benefit of detailed STF follow-up investigations is the ability to identify the

role of risk factors and their interactions in injury events, including the presence and role

of latent failures (Reason 1990, Wagenaar 1998). Indeed, table 5 shows work

organization factors played a key role in STF injuries investigated. Time pressure was

common to a large number of incidents and often motivated unsafe or time-saving

behaviours that contributed to STF. Time pressure was reported as an inevitable

consequence of variations in workloads over time, minimization of staff numbers,

seasonal fluctuations and the semi-paced nature of the work itself.

A range of design factors was also identified as contributory for dairy farming STF,

including equipment design errors. Design weaknesses included the absence of safe

positioning for feet when climbing on/off equipment, the necessity to improvise and climb

around plant and vehicles to view aspects of the task (e.g. due to a lack of viewing panel

to observe vat content levels). Apparel design and fit issues were also identified, with cases

involving ill-fitting protective clothing due to production of an inadequate size range by

the manufacturer. Design factors were found to commonly interact with the presence of

slippery underfoot conditions in dairy farming. It was common for cases to involve

slippery underfoot conditions, worn footwear tread (or inappropriate footwear design

and selection) and rushing (running or moving too quickly for underfoot conditions) in

combination.

Table 5. Key risk factors for dairy farming slip, trip and fall cases investigated

Cases factor present

Key risk factor (n) (%) Factor classification

Running, short cut 24 60 Behavioural

Design of plant and equipment 24 60 Design

Work organization (particularly time pressure) 24 60 Work organization

Water or other surface contamination 20 50 Physical environment

Inappropriate/worn footwear 20 50 Design/behavioural

Concurrent visual task 19 48 Task

Poor injury assessment 19 48 Individual – decisional

Uneven/obstructed underfoot surface 10 25 Physical environment

Pre-existing injury 10 25 Individual – physical

Unpredictable cattle behaviour 8 20 Environmental

Housekeeping 7 18 Behavioural/environmental

Maintenance/equipment failure factors 7 18 Equipment

Fatigue 6 15 Individual – physical

Working alone 5 13 Work organization

Slips, trips and falls 1015

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

The presence of concurrent visual tasks – to be undertaken at the same time as walking

and/or monitoring a hazardous underfoot environment (Marletta 1991, Haslam and

Bentley 1999, Kines 2003) was observed for a relatively large number of cases investigated

(45%). This chronic task vs. locomotion problem has been well documented by other

researchers as being critical to STF risk. For example, Haslam and Bentley (1999) found

postal delivery employees in the UK to frequently incur STF as a direct consequence of

not identifying or recognizing an underfoot hazard due to task distraction: reading or

sorting mail for the next delivery point. Kines (2003), applied an information processing

model to occupational falls from heights and identified cases where task factors caused

workers to be ‘temporarily inattentive to the boundaries of the work surface’. Marletta

(1991) outlined how such visual distraction related to the task of the person in

locomotion can increase STF risk, as the pedestrian is unable to adopt the appropriate

gait for the underfoot conditions. Clearly, any task undertaken in a relatively

uncontrolled industrial environment where effective housekeeping is not always possible,

such as those encountered commonly in dairy farming, will be particularly vulnerable to

this risk. The major problematic concurrent visual task while walking in cases

investigated was the need to watch cattle closely during stock movement or milking-

related activities. This factor was identified as a risk where it contributed to the injured

worker not seeing the underfoot hazard involved in the STF (e.g. a sudden change in

surface friction characteristics or abrupt vertical protrusion). Aspects of task design may

play a role in exaggerating this problem for certain activities. This factor occurred in

combination with rushing/sudden movement and slippery underfoot conditions in several

cases.

Behavioural factors, specifically running, moving quickly, sudden movement or taking

short cuts (e.g. jumping down from platforms or over gates), were also found to be

contributory in a large number of STF cases investigated (60%). Running was often a

factor as workers were working alone in situations not designed (effectively) for solo

operation. Moreover, rushing or sudden movement, to head off an animal or operate a

gate, was often undertaken in the presence of a contaminated or unpredictable underfoot

surface. Rushing frequently interacted with the use of inappropriate or worn footwear,

often being used in the presence of very slippery and/or damaged underfoot conditions

(e.g. old concrete steps).

3.7. Secondary and tertiary injury factors

Failure to adequately assess the extent of the injury incurred as a result of the STF

and/or failure to seek medical attention and/or stop work upon incurring a major

injury was frequently observed for dairy farming STF. Some 48% of STF cases

investigated involved injured workers continuing with their normal work, sometimes in

severe pain or discomfort, following the STF event. In the majority of cases this

occurred as a direct consequence of having no one to take over essential tasks that

had to be completed at that time (e.g. milking – see comments above on solo

operation issues), although a few claimants noted they were not at first fully aware of

the extent of their injury. Furthermore, many claimants continued to work on for

several days before seeking medical attention, potentially making their injuries worse

and associated recovery periods longer. From interviews with these claimants it was

apparent that cover for their duties was difficult to get at short notice and no

claimants noted having contingency plans in place beyond the help of family members

for cases such as these.

1016 T. Bentley et al.

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

3.8. Efficacy of the detailed follow-up investigation methodology

Detailed information on a range of key contributory risk factors has been produced

through the use of this investigation methodology. It is clear that the ability to identify

key risk factor combinations provides the strongest evidence for STF causation. For the

dairy farming STF investigated, for example, the presence of slippery underfoot

conditions caused by a range of contaminants and the use of worn and unsuitable

footwear are risk factors that frequently occurred in combination. Likewise, various plant

design weaknesses and the use of unsafe behaviours appear to be factors linked in the

complex aetiology of dairy farming STF. Concurrent visual tasks and walking/running

have been strongly linked, particularly in the presence of unsafe underfoot conditions.

The ability to identify such risk factor interactions is crucial from the perspective of an

ergonomics model of occupational injury.

Importantly, the specific organizational and cultural context surrounding each STF

event has been understood as a vital component of this approach to STF investigation

(Shaw and Blewett 1998). The ability to place the role of each contributory risk factor

within the temporal sequence of incident events using the Events and Contributory

Factors Chart (Haslam and Bentley 1999) has further supported this approach, providing

a simple means of recording and reporting summary event and risk factor information to

aid subsequent analysis and summation of key issues. Of particular benefit is information

about latent failure/factors in STF risk, such as work organization, task and physical

design shortcomings. Each of these areas of latent failure and risk has been shown to be

central to STF events in cases investigated. In addition, the use of such a model allows for

the collection of pre- and post-incident information. A good example of the usefulness of

such analysis is the tertiary safety issue identified from STF cases, where injured workers

in this sector are at considerable risk of further exacerbating the extent of their injury and

subsequent recovery time by working on following relatively serious injuries. Moreover,

the role of historical injury experiences and the impact of previous injuries to the same

body part also improve understanding of injury causation.

The advantages of the follow-up investigative approach must be weighed against the

many logistical problems that follow-up investigations present. As Bentley and Haslam

(2005) observed, this method of investigation is time- and labour-intensive and therefore

costly. Reliance on the cooperation of the STF injured person presents a further

challenge. This is exacerbated by ethical and privacy concerns, including complex

participant contact methods necessitated by the need to protect the claimant’s identity,

leading to low response rates. Furthermore, in some cases it was not possible to interview

the STF injured worker at the injury site; this factor represented an important limitation

in the present study. The use of the Events and Contributory Factors Chart and other

measures to aid participant recall for events went some way to overcoming this problem.

This instrument was particularly useful for a small number of events where the

respondent did not have sufficient time to answer all the detailed questions contained in

the third section of the questionnaire. In these cases the researchers were able to gather

and record, in a structured manner, sufficient information to allow the identification of

key events and contributory factors, including contextual and pre/post event factors.

These data formed a basis to be further elaborated upon on later contact with the

respondent.

While further work is required to improve this investigative technique, it may be

concluded that the detailed follow-up investigation methodology and its tools are an

effective way to produce high-quality risk factor information necessary for the

Slips, trips and falls 1017

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

development of research-based interventions in occupational settings. Further research

targeting intervention design and evaluation will proceed from a solid base of

information that, arguably, could have only been provided through the methods used

in this study.

4. Conclusions

This study was the first in New Zealand and internationally to focus on STF in the dairy

farming sector. Findings from the detailed follow-up investigations have provided

information about risk factors and their interactions that goes beyond that obtainable

through the analysis of secondary data on STF events, such as that conducted in the first

phase of this programme of research, in terms of allowing the identification and analysis

of key risk factor interactions. The information gathered on key risk factors for dairy

farming STF is presently informing the development of interventions to address the STF

problem in this sector.

While the use of site investigations and injured employee interviews is not new to safety

research, this approach is often reserved for the investigation of individual occupational

incidents, rather than multiple relatively low-hazard events such as STF in a specific

population group. The use of an Events and Contributory Factors Chart has proved to

be an important component of this research methodology, helping to standardize data

collection for each event across different event stages. Further research should examine

the efficacy of this research methodology, including the investigation of STF in other

occupational settings. Ergonomics and injury prevention researchers might also consider

the application of this technique of risk factor identification to other areas of injury

concern.

Acknowledgements

The authors gratefully acknowledge the support of the Health Research Council of New

Zealand, The ACC and the Department of Labour’s Occupational Safety and Health

Division. The authors would also like to thank the participants and their families, who so

generously gave of their time to participate in this project.

References

ACCIDENT COMPENSATION CORPORATION, 1999, Analysis of Work Related Injuries: Construction. (Wellington,

New Zealand: ACC).

BENTLEY, T. and HASLAM, R., 2001, Identification of risk factors and countermeasures for slip, trip and fall

accidents during the delivery of mail. Applied Ergonomics, 32, 127 – 134.

BENTLEY, T.A. and HASLAM, R.A., 2005, Epidemiological approaches to investigating causes of slip, trip and fall

injuries. In R. Haslam and D. Stubbs (Eds.), Understanding and Preventing Fall Accidents (London: Taylor

and Francis) (in press).

BENTLEY, T.A. and TAPPIN, D.C., 2004, An exploratory analysis of slips, trips and falls in New Zealand dairy

farming. Journal of Occupational Health and Safety – Australia and New Zealand, 20, 131 – 138.

COTNAM, W., CHANG, W.-R. and COURTNEY, T., 2000, A retrospective study of occupational slips, trips and falls

across industries. In Ergonomics for the New Millenium Proceedings of the XIVth Triennial Congress of the

International Ergonomics Society, August 2003, San Diego, California, USA. (Santa Monica, California,

USA: Human Factors and Ergonomics Society). pp. 473 – 476.

DAVID, G. and RIDD, J., 2001, STFA ‘98: An international conference on slipping, tripping and falling accidents.

(Editoral). Applied Ergonomics, 32, 117 – 118.

1018 T. Bentley et al.

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14

GRONQVIST, R., 1999, Slips and falls. In Biomechanics in Ergonomics, S. Kumar (Ed.), pp. 351 – 375 (London:

Taylor & Francis).

HASLAM, R.A. and BENTLEY, T.A., 1999, Follow-up investigations of slip, trip and fall accidents among postal

delivery workers. Safety Science, 32, 33 – 47.

KINES, P., 2003, Case studies of occupational falls from heights: cognition and behaviour in context. Journal of

Safety Research, 34, 263 – 271.

LEAMON, T. and MURPHY, P., 1995, Occupational slips and falls: More than a trivial problem. Ergonomics, 38,

487 – 498.

MANNING, D.P. and JONES, C., 2001, The effect of roughness, floor polish, water, oil and ice on underfoot

friction: current safety footwear solings are less slip resistant than microcellular polyurethane. Applied

Ergonomics, 32, 185 – 196.

MARLETTA, W., 1991, Trip, slip and fall prevention. In The Work Environment, Vol. 1: Occupational Health

Fundamentals, D. Hansen (Ed.), pp. 241 – 261 (Chelsea, Michigan: Lewis Publishers).

NATIONAL INSTITUTE FOR OCCUPATIONAL SAFETY and HEALTH, 2000, Worker Deaths by Falls: A Summary of

Surveillance Findings and Investigative Case Reports. (Washington, DC: US Department of Health and

Human Services, National Institute for Occupational Safety and Health, September 2000).

NATIONAL OCCUPATIONAL HEALTH and SAFETY COMMISSION, 1998, Work-related Traumatic Fatalities in

Australia 1989 – 1992. (Canberra: Commonwealth of Australia 1998).

OCCUPATIONAL SAFETY and HEALTH, 2001,Workplace Accident Insurance Statistics Report 2000/01. (Wellington,

New Zealand: Department of Labour).

PARKER, R., BENTLEY, T. and ASHBY, L., 2002, Forestry applications of human factors research. In Handbook of

Human Factors Testing and Evaluation, 2nd edition, T.G. O’Brien and S.G. Charlton (Eds.) (Mahwah, NJ:

Lawrence Erlbaum Associates).

RAMSEY, J., 1985, Ergonomic factors in task analysis for consumer product safety. Journal of Occupational

Accidents, 7, 113 – 123.

REASON, J., 1990, Human Error. (New York: Cambridge University Press).

SHAW, A. and BLEWETT, V., 1998, Before it’s too late: evaluating the effectiveness of interventions. In

Occupational Injury. Risk, Prevention and Intervention, A.-M. Feyer and A. Williams (Eds.), pp.195 – 203

(London: Taylor & Francis).

TISSERAND, M., 1985, Progress in the prevention of falls caused by slipping. Ergonomics, 28, 1027 – 1042.

WAGENAAR, W., 1998, People make accidents but organisations cause them. In Occupational Injury. Risk,

Prevention and Intervention, A.-M. Feyer and A. Williams (Eds.), pp.121 – 128 (London: Taylor & Francis).

Slips, trips and falls 1019

Dow

nloa

ded

by [

Ban

gor

Uni

vers

ity]

at 2

0:51

19

Dec

embe

r 20

14