a iliii li i 111 ii - dtic

USAARL Report No. 94-41

AD-A285 199

Whole-body Vibration Assessmentof the M1070 Heavy Equipment Transporter

Volume 1

By

Tammy L. SimmonsBarclay P. ButlerNabih M. Alem

Bradley S. Erickson

Aircrew Protection Division

A '*J64-31396August 1994 Iliii li I 111 ii

Approved for public release; distribution unlimited.

United States Army Aeromedical Research Laboratory

Fort Rucker, Alabama 36362-0577

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The views, opinions, and/or findings contained in this report arethose of the author(s) and should not be construed as an officialDepartment of the Army position, policy, or decision, unless sodesignated by other official documentation. Citation of tradenames in this report does not constitute an official Departmentof the Army endorsement or approval of the use of such commercialitems.

Human use

Human subjects participated in these studies after giving theirfree and informed voluntary consent. Investigators adhered to AR70-25 and USAMRDC Reg 70-25 on Use of Volunteers in Research.

Reviewed:

KEVIN T. MASONLTC, MC, MPSDirector, Aircrew Protection

Division

Released for publication:

RO WILE D., Ph.D. DENNIS F. SHANAHANChairman, Sientific Colonel, MC, MFS

Re ew Committee Commanding

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USAARL Report No. 94-41, Volume 1

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U.S. Army Aeromedical Research (If applicable) U.S. Army Medical Research, Development,Laboratory SGRD-UAD-IV Acquisition and Logistics Command6c. ADDRESS (City, State, and ZIP Code) 7b. ADDRESS (City, State, and ZIP Code)P.O. Box 620577 Fort DetrickFort Rucker, AL 36362-0577 Frederick, MD 21702-5012

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PROGRAM I PROJECT TASK WORK UNITELEMENT NC NO. NO. IACCESSION NO.62787A 30162787A87 3FA I 145

11. TITLE (include Security Clssification)

Whole-body vibration assessment of the M1070 Heavy Equipment Transporter

12. PERSONAL AUTHOR(S)Tammy L. Simmons, Barclay P. Butler, Nabih M. Alem and Bradley S. Erickson13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (Year, Month, Day) 15. PAGE COUNT

FROM TO 1994 AugustI 1816. SUPPLEMENTARY NOTATION

17. COSATI CODES 18. SUBJECT TERMS (Continue on reverse if necessary and identify by block number)

FIELD GROUP SUB-GROUP Whole-body vibration, health hazard assessment, exposure05 09 limits, tactical vehicles, terrain, crewmembers20 11

19. ABSTRACT (Continue on reverse if necessary and identify by block number)An evaluation of all new tactical vehicles and aircraft is required to assess potentialwhole-body vibration (WBV) health hazards to crewmembers. As requested by the U.S. ArmyEnvironmental Hygiene Agency (USAEHA), a health hazard assessment (HHA) was performed by theU.S. Army Aeromedical Research Laboratory (USAARL) on the M1070 Heavy Equipment TransporterSystem (HETS). The HETS was tested on three cross-country courses at Aberdeen ProvingGround (APG), MD, by the U.S. Army Combat Systems Test Activity (USACSTA), in coordinationwith the Response and Tolerance Branch of USAARL. The M1070 HETS was tested with a M1000trailer in a loaded and unloaded configuration. The loaded configuration was obtained byplacing an Ml tank on the bed of the M1000 trailer. The unloaded configuration consisted ofa M1070 tractor with an empty M1000 trailer. While operating the HETS in its intendedoperational environment, the front passenger was exposed to an overall risk assessment codeof 5. This consisted of an overall assignment of hazard severity category IV and hazardprobability level D.

Volume 1 describes the tests and discusses the results. Volume 2 contains Appendix B, thedata plots and graphs.20. DISTRIBUTION /AVAILABILITY OF ABSTRACT 21- ABSTRACT SECURITY CLASSIFICATION

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'nowledgmenýs

The authors would 1.-e to express their gratitude to Mrs.Mary Gramling for her commendable efforts in editing of thisreport.

Accesion For

NTIS CRA&IDTIC TABUran XLoimcedJ- -tii-- .. . .....................

By ...... ...........

Avw ;iJility Cocies

Av , ý2>1d j orDist I'Pucial

This page intentionally left blank.

ii

Table of contents

Page

List of figures ..................... ...................... 2

List of tables ..................... ...................... 2

Introduction ...................... ....................... 3

Methods ................................. 4

Results .................... .......................... 11

Discussion ................. ........................ 14

Conclusions .................. ......................... 15

References o... ...... ......................... o..17

Appendix A: Manufacturers' list ......... .............. 18

List of figures

Figure Page

1. Heavy equipment transport system ........ .......... 3

2. Data acquisition system . .................. 6

List of tables

Table Page

1. WBV test matrix . ...................... 5

2. Hazard severity classification .... ............. . 8

3. Hazard probability classification .. ........... 9

4. Hazard probability classification with testoperating conditions . . . . . ............. 10

5. RAC determination . . . . . . . . . ........

6. Driver seat HSEL for minimal exposure timeswith respect to axis, vibration frequency,vehicle speed, and test course ........... . . 12

7. Front passenger seat HSEL for minimal exposuretimes with respect to axis, vibration frequency,vehicle speed, and test course ... .......... . . . 13

8. Roadside passenger seat HSEL for minimal exposuretimes with respect to axis, vibration frequency,vehicle speed, and test course . . ........... 13

9. Curbside passenger seat HSEL for minimal exposuretimes with respect to axis, vibration frequency,vehicle speed, and test course . . . . . . . .... 14

2

Introduction

It is a requirement of Army Regulation (AR) 40-10, Healthhazard assessment program in suRDort of the Army materiel ac•G~isition process, that an evaluation for potential whole-bodyvibration (WBV) health hazards be conducted on all new tacticalvehicles and aircraft to survey the risk to their crewmembers.In support of this program, the U.S. Army Environmental HygieneAgency (USAEHA) requested the U.S. Army Aeromedical ResearchLaboratory (USAARL) to perform a health hazard assessment (HHA)on the M1070 heavy equipment transporter system* (HETS) truck.

The HETS, shown in Figure 1, is an all-wheel drive (8x8)commercial vehicle manufactured by the Oshkosh Truck Corpora-tion*. The M1070 HETS was built to fill the need of transportingthe M1 Abrams main battle tank (MBT). The HETS is powered by aDetroit Diesel 8V-92TA diesel engine* generating 500 hp and has a5-speed automatic Allison transmission*. The HETS is capable ofattaining a maximum speed of 52 km/h and has a range of 724 km.

Figure 1. M1070 heavy equipment transporter.

* See manufacturers' list.

3

The HETS has a typical configuration consisting of a fullycovered ca., a crew capacity of five, and is designed to tow theM1000 semitrailer. The standard M1070 HETS is equipped with twowinches, each having a 25-ton load capacity. The nominal load onthe fifth wheel of the vehicle is 20,866 kg. The HETS has a curbweight of 18,598 kg and is transportable in the C-5A aad C-17transport aircraft. The physical characteristics of the M1070HETS, combined with vehicle speed, load, terrain, and crewmemberposition, result in a unique WBV signature whose measurement andevaluation are the subject of this report.

The methods for measuring and analyzing WBV are found in theInternational Organization for Standardization's (ISO) guidelineentitled "Guide for the evaluation of human exposure to whole-body vibration (ISO 2631)." ISO 2631 is reflected in MIL-STD-1472D, "Human engineering design criteria for military systems,equipment and facilities." The relative severity of the pro-cessed WBV signatures are interpreted using the risk assessmentcodes (RAC) found in AR 40-10. As a set, these publicationsdefine the methods and criteria used in evaluating the WBVsignatures of the M1070 HETS.

ISO 2631 identifies three criteria for the evaluation ofhuman exposure to WBV which can be described in terms of inten-sity, frequency, direction, and duration. These criteria are thepreservation of comfort, the preservation of working efficiency,and the preservation of health and safety. They are knownformally as the reduced comfort boundary (RCB), fatigue-decreasedproficiency boundary (FDPB), and health and safety exposure limit(HSEL), respectively.

The RACs, as described in AR 40-10, Appendix B, require theclassification of a health hazard according to its severity andprobability. Processing vibration signatures using ISO-2631results in measurements of vibration severity, but does not yielda measure of the probability of occurrence. Therefore, RACs alsoare used and are obtained by combining vibration severity withthe probability that the test condition will occur in a real lifescenario. For vibration, RACs would be determined for eachvibration amplitude at each direction and frequency.

Methods

The WBV data on the M1070 HETS were collected at AberdeenProving Grounds (APG), Maryland. A test matrix was developedthat represented the planned operating environment of the M1070HETS with respect to terrain type and vehicle speed (Table 1).

4

Table 1.

Test matrix for WBV testing of the M1070 HETS.

Test courses

Speed Paved road Cross-country #2 Secondary road(mph)

Loaded Unloaded Loaded Unloaded Loaded Unloaded

5 X X

10 X X X

15 X X X X

20 X X

25 X X X X

30 X X X

35 X X

40 X X ___

Experimental conditions

The M1070 HETS was tested over three courses with a MI000trailer in a loaded and unloaded configuration. Exact charac-terizations of the three test tracks can be obtained from APG.The loaded configuration was obtained by placing an Ml tank onthe bed of the M1000 trailer. The unloaded configuration con-sisted of a M1070 tractor with an empty M1000 trailer.

The HETS was tested with vehicle speeds ranging from 5 to 40mph. Specific vehicle speeds were selected in order to mirrorlikely employment scenarios for each test course. On the cross-country #2 course, the HETS was tested at 5, 10, and 15 mph forboth the loaded and unloaded case. Secondary course test speedswere 15, 20, and 30 mph for the loaded case, and 20, 25, and 30mph for the unloaded case. On the paved course, the HETS wastested at 30, 35, and 40 mph for both the loaded and unloadedconfiguration.

5

Instrumentation

Seat pad accelerations were obtained in the X-, Y-, and Z-axes for the driver, front-seated passenger, and the two rearseated passengers located on the road-side seat and the curb-sideseat. The rear-seated center passenger location accelerationswere not measured. Three Endevco* model 2265C-25 accelerometers,in a triaxial arrangement, were attached to disks placed betweenthe seat pad and the subject's buttocks. Each of the accelerom-eters were connected to a signal conditioner which providedexcitation, amplification, calibration, and low pass filtering.The accelerometers were low pass filtered at 100 Hz using a six-pole Butterworth filter. A diagram of the data acquisitionsystem is included as Figure 2.

Filtered acceleration signals from the signal conditionerwere connected to an EMR* model 372-03 pulse code modulation(PCM) encoder. The encoder multiplexed the incoming analogsignals which then were sampled at 416.67 Hz per channel. Theincoming analog signal was sampled using a sample-and-holdamplifier, digitized using a 10-bit successive approximationanalog-to-digital converter, anJ then converted to a nonreturn-to-zero level (NRZ-L) code for transmission. The encoded PCMdata then was input to a Conic* model CTL 510 transmitter fortransmission at 237 MHz to the remote data handling facility.The signal conditioner, encoder, and transmitter were mounted onthe back of the HETS cab during the entire test.

TrndcrSignal PCM

conditioner encoderTransducer

Loral ADS 100I l PCM bit I I PCM / .ralrl--el~--

V "--'R eiver synchronizer decommutator input CPU - D

FigurePCM.Daac Dqustin Dsgitalerecorder converter tapes

I time I . I

S ISc°pes Analyzerl

Figure 2. Data acquisition system.

6

The transmitted NRZ-L code was received by a ScientificAtlanta* series 420S receiver and passed into a Loral Instrumen-tation* ADS-100 system. The input buffer and PCM bit synchro-nizer modules recovered the serial pulse train from the data linknoise and disturbances. The pulse train was recorded on aHoneywell* model 101 PCM tape recorder along with voice annota-tion of the individual test runs and an IRIG-B time code. Simul-taneously, the PCM pulse train was passed to a PCM decommutatorand demultiplexed into 16-bit words.

From this point, the pulse train was sent to both a digital-to-analog (D/A) converter and a parallel input module. The D/Aconverter passed the pulse train through a filter, external tothe ADS-100 system, for real time display and Fourier analysis.The parallel input module was used to input digital IRIG-B timecode into the ADS-100. The pulse train passed out of the ADS-100system from the input idule to the host computer, a Hewlett-Packard* (HP) model 21MX-E series minicomputer. The data werestored temporarily on the HP system disk and later transferred todigital tape to provide a permanent storage medium. The ADS-100system was independent of the host control: however, softwareresiding un the minicomputer controlled the handshaking betweenthe ADS-100 and the HP21MX-E during data acquisition.

Analysis

Triaxial seat pad vibration data were processed using themethods prescribed in ISO 2631 for broadband signals using third-octave analysis with weighting. Digitized acceleration signalsfrom the X-, Y-, and Z-axis from both the driver and passengerseat pad accelerometers were read into a Dolch* model 486 port-able computer. A USAARL-developed automated analysis program wasused to produce tabular and graphic plots of the accelerationdata. These plots (Appendix B) were used to identify vibrationexposure limits which occurred under projected normal dailyoperating conditions.

The exposure data then were classified using the RACs from AR40-10. The RACs require classification of the health hazardaccording to the hazard severity and probability. Since the ISO2631 standard does not use RACs, the severity of the hazardreasonably may be estimated from worst-case exposure before theonset of the HSEL for each vibration frequency and direction. Anindicator which may be used for the assessment of hazard severityis the duration of safe exposure (DSE). The DSE is defined asthe length of time a person can be exposed to WBV before reachingthe HSEL. Thus, a long DSE indicates tolerable WBV, whereas ashort DSE indicates severe WBV. In order to t:anslate the DSEsto RACs, Table 2 was used to define the category (I-IV) ofexposure.

7

Table 2.

Hazard severity classification.

Attribute Category WBV duration of safe exposure

Catastrophic I Less than 5 minutes

Critical II Between 5 and 30 minutes

Marginal III Between 30 minutes and 4 hours

Negligible IV More than 4 hours

Hazard severity categories are defined as:

Category I Catastrophic: Hazard may cause death ortotal loss of a bodily system.

Category II Critical: Hazard may cause severebodily injury, severe occupationalillness, or major damage to a bodilysystem.

Category III Marginal: Hazard may cause minor bodilyinjury, minor occupational illness, orminor damage to a bodily system.

Category IV Negligible: Hazard would cause lessthan minor bodily injury, minoroccupational illness, or minor bodily

_system damage.

The operational environments of the HETS determine the like-lihood of occurrence, or probability level, of exposure to WBV.These levels, identified in AR 40-10 as levels A through E, withtheir corresponding descriptions, are listed in Table 3. Theprobability levels for each test condition relevant to the WBVsignatures in the HETS are listed in Table 4. Table 4 also givesthe weighted probability calculated using a coding of 50 - 10 forprobability level A - E, respectively. This is divided by thetotal of the coded probability level for each mission percentagetime, and multiplied by the mission percentage. Weighted prob-abilities A' - E' were found using natural breaks in the sortedweighted probabilities with A'>7, 3<B'<7, 1<C'<3, and D'<1percent. No weighted probability is given for E' although testengineers at APG suggested this would cover those times the HETSwas operated in a bobtail configuration.

8

Table 3.

Hazard probability classification.

Attribute Level Specific individual FA L item I Fleet or inventory

Likely to occur ContinuouslyFrequent A frequently experience

Will occur severalProbable B times in the life Will occur frequently

of an itemLikely to occurLikel to ccurWill occur several

Occasional C sometime in the Wil c elife of an item

Unlikely but Unlikely but can be

Remote D possible to occur reasonably expected toin the life of an ritem occur

So unlikely, it can

Improbable E b- assumed Unlikely to occur, buto:currence may not possible

_be experienced

9

Table 4.

Hazard probability classification with test operating conditions.

Percent- Proba- Weighted WeightedTerrain age of Config- Speed Proba- bility proba- proba-

mission uration (mph) bility level bility bilitytime level

10 Frequent A 13.158 A'50 Loaded

Secondary 15 Frequent A 13.158 A'road 20 Frequent A 13.158 A'

25 Probable B 10.526 A'

15 Frequent A 1.316 C'5 Unloaded

20 Frequent A 1.316 C'

25 Frequent A 1.316 C'

30 Probable B 1.053 C'

25 Frequent A 7.368 A'

28 Loaded 30 Frequent A 7.368 A'Pavedroad 35 Frequent A 7.368 A'

40 Probable B 5.895 B'

25 Probable B 0.444 D_

2 Unloaded 30 Probable B 0.444 D'

35 Frequent A 0.556 D'


5 Probable B 4.000 B'14 Loaded

Cross- 10 Frequent A 5.000 B'country 15 Frequent A 5.000 B'

5 Probable B 0.308 D'1 Unloaded

10 Probable B 0.308 D'


10

Hazard severity categories and hazard probability levels areused to find the RACs for each test condition. Using Table 5,the RACs are found at the intersection of the Hazard Category andProbability Level, here using the primed levels. The overall RACfor the vehicle is determined by averaging and rounding theindividual RACs.

Table 5.

RAC determination.

Hazard probability levels

Hazard A B C D Ecategory

I 11 12 3

II11 2 3 4

111 2 3 3 45

IV 3 5 5 5 5

Results

The duration of exposure to reach the HSEL was calculated forall 216 data sets. The minimum durations for HSELs were foundfor each position, terrain, speed, and load for each of the fourseating positions--driver, front passenger, roadside passenger(RS),. and curb-side passenger (CS)--and are shown in Tables 6, 7,8, and 9, respectively. These tables are arranged in order ofincreasing levels of DSE. Since the HETS requires 10 hours oftotal mission time in any 24-hour period, the exposure limits ofless than 10 hours were flagged for assessment. The DSE isdetermined from the time required to reach the HSEL (Appendix B)according to ISO-2631. The RACs shown are a measure of thehazard severity of the test condition and are based on the DSE,course terrain, and speed.

The worst case exposure limits were determined from eachseating position's lowest DSE. The DSEs below 10 hours werefound only for the front passenger seating position underunloaded conditions. Two cases were flagged for assessment: aDSE of 8 hours 4 minutes at a vehicle speed of 15 mph on cross-country terrain (Appendix B, run number 14), and a DSE of 8 hours52 minutes at a vehicle speed of 30 mph on paved roads (Appendix

11

B, run number 20). Both DSEs occurred in the Z axis atfrequencies of 2.0 and 3.9 Hz, respectively. The hazard severityassigned to these two conditions were found to be Category IVfrom the DSE ranges of Table 2. Weighted hazard probabilitiesfor these two conditions were combined with hazard categoriesusing Table 5 to yield RACs of 5. With only two test conditionsyielding RACs of 5, this vehicle is assigned an overall RAC of 5.

Table 6.

Driver seat HSEL for minimal exposure times with respect to axis,vibration frequency, vehicle speed, and test course.

Determination of hazard severity Determination of probability level Over-all

RAC

DSE A Hazard H zOrd Test Configu- Speed probd- ability

(h:m) Axis Hz severity ute- course ration (mph) bility abilityj _____ gory ________ levelj ____ _____

8:52 Z 3.9 Negligible IV Paved Unloaded 30 Remote D0 5

10:22 Z 1.6 Negligible IV CC #2 Unloaded 15 Remote D' 5

13:18 Z 2.5 Negligible IV CC #2 Unloaded 20 Remote D. 5

14:00 Z 2.0 Negligible IV Secondary Loaded 20 Frequent A 3

15:18 Z 2.0 Negligible IV Secondary Loaded 15 Frequent A' 3

18:45 Z 2.5 Negligible lV4 Paved Loaded 25 Frequent A' 3

12

Front passenger seat HSEL for minimal exposure times with respectto axis, vibration frequency, vehicle speed, and test course.

Determination of hazard severity Determination of probability level

Over-- -all

DSE Hazard Hazard Test Configu- Speed Hazard Probe- RAC

lh:m) Axis Hz severity Ca- course ration (mph) probe- biitygory bility level

8:04 Z 2.0 Negligible IV CC 12 Unloadod 15 Remote D' 5

11:02 Z 3.9 Negligible IV Secondary Unloaded 30 Remote C' 5

12:08 Z 2.5 Negligible IV Paved Loaded 25 Frequent A' 3

14:33 Z 5.0 Negligible IV Paved Unloaded 40 Probable B' 5


16:25 Z 2.0 Negligible IV CC 12 Loaded 15 Occasional B' 5

Table 8.

Roadside passenger seat HSEL for minimal exposure timeswith respect to axis, vibration frequency,

vehicle speed, and test course.

Determination of hazard severity Determination of probability level

Over-

DSE Hazard Hazard Test Configu- Speed Hazard Frob- RAC

(h:m) Axis Hz severity Oate- course ration (mph) probe- I abilitygory bility level

12:30 Z 1.6 Negligible IV, CC #2 Unloaded 15 Remote D' 5

15:41 Z 3.9 Negligible IV Paved Unloaded 30 Remote D' 516:37 Z 5.0 Negligible IV CC #2 Unloaded 20 Remote 0' 5



19:45 Z 2.0 Negligible IV CC #2 Loaded 15 Occasional 8' 5

13

Table 9.

Curb side passenger seat HSEL for minimal exposure timeswith respect to axis, vibration frequency,

vehicle speed, and test course.

Determination of hazard seventy Determination of probability level

Over-

I IIProb al(h:m) Axis Hz severity *&te course ration (ph) babilit

goryourse C on S pee bility y

level

10:12 Z 2.0 Negligible IV CC #2 Unloaded 15 Remote 5

13:23 Z 3.9 Negligible IV Secondary Unloaded 30 Occasional C' 5

14:07 Z 5.0 Negligible IV Paved Unloaded 40 Remote 0' 5



20:17 Z 2.0 Negligible IV CC #2 Loaded 15 Probable B' 5

Discussion

Whole-body vibration exposures for the M1070 HETS that wereless than the required 10-hour operational period were found foronly two conditions. Both these conditions were in the unloadedconfiguration and occurred on cross-country and paved terrain.These scenarios were projected to have a low probability ofoccurrence which resulted in a weighted probability level of D,or remote, for both instances. The hazard category was identi-fied as IV with both DSEs being greater than 4 hours. The hazardprobability of D, combined with the hazard category of IV,resulted in an overall RAC of 5 implying a low risk level with adecision making authority residing with the program manager (AR40-10).

The two hazardous WBV exposure conditions that were foundoccurred at the front seat positions only. The driver positionreceived a DSE of less than 10 hours on the paved terrain, andthe front seat passenger received a DSE of less than 10 hours forcross-country terrain. No hazardous WBV exposures were found forthe rear seated passengers under loaded conditions--a configu-ration likely to occur when the M1 tank crew would be riding inthe HETS passenger compartment.

14

The frequency of the hazardous WBV exposures were found tobe --.0 Hz and 3.9 Hz for the driver and front seat passenger,respectively. This trend for a large vibration amplitude at lowfrequencies was seen in most of the HETS vibration signatures.This low-level frequency response is unusual for heavy equipmentwith most off-road vehicles showing resonant WBV peaks in the 4-8Hz range. A potential explanation for this low frequency contentis that the seating/suspension system could be very soft result-ing in a very low resonant frequency.

The WBV experienced by the vehicle crewmen differed forseating position. The front seat positions typically showed datawith lower HSELs as compared to the rear seat passenger positionsfor most of the data trials. A review of the plotted data ofAppendix B shows that the rear seated passengers typically hadlower amplitude low frequency components and higher amplitudehigh frequency components. This implies that the rear seatingsystems are stiffer than the front seat positions showing lessgain in the low frequency bands and more transmission in thehigher frequency bands.

Conclusions

While operating the HETS in its intended operationalenvironment, the front passenger was exposed to an overall RAC of5. This consisted of an overall assignment of hazard severitycategory IV and hazard probability level D. It is recommendedthat exposure to WBV be restricted to:

a. Paved surface at vehicle:

(1) Unloaded trailer configuration: not more than 9hours continuous operation in any 24-hour period speeds less than30 mph.

(2) Loaded trailer configuration: not more than 12 hourscontinuous operation in any 24-hour period speeds less than 25mph.

b. Cross-country terrain:

(1) Unloaded trailer configuration: not more than 8hours continuous operation in any 24-hour period at vehiclespeeds less than 15 mph.

(2) Loaded trailer configuration: not more than 15 hourscontinuous operation in any 24-hour period at vehicle speeds lessthan 15 mph.

15

c. Secondary terrain:

(1) Unloaded trailer configuration: not more than 11hours continuous operation in any 24-hour period at vehiclespeeds less than 30 mph.

(2) Loaded trailer configuration: not more than 14 hourscontinuous operation in any 24-hour period at vehicle speeds lessthan 20 mph.

16

Department of the Army. 1991. Health hazard assessment programin support of the Army material acquisition decisionVxDr&,,%a. Washington, DC: Department of the Army. AR 40-10.

Department of Defense. 1989. Human engineering design criteriafor military systems. equipment and facilities. Washington,DC: Department of Defense. MIL-STD-1472D.

Foss, Christopher F., and Gander, Terry J., eds. 1993. Jane'smilitary vehicles and logistics. Alexandria, VA: Jane'sInformation Group, Inc.

International Organization for Standardization. 1985.Evaluation of human exposure to whole-body vibration. Part1: General reQuirements. ISO-2631. 2nd edition.1985-05-15.

U.S. Army Environmental Hygiene Agency. Memorandum, HSHB-MO-A, 5August 1993, subject: Health Hazard Assessment Report (HHAR)on the Heavy Equipment Transporter System (HETS).

17

Appendix A.

Manufacturers' list.

Conic/Loral Data Systems9020 Balboa AvenueSan Diego, CA 92123

EMR/Fairchild Weston SystemsP.O. Box 3041Sarasota, FL 33578

HoneywellHoneywell PlazaMinneapolis, MN 55408

Hewlett-Packard Company4700 Bayou BoulevardPensacola, FL 32502

Loral Instrumentation8401-T Aero Dr.San Diego, CA 92123

Oshkosh Truck CorporationPO Box 2566Oshkosh, WI 54903

18

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Commander, U.S. Army Research U.S. Army Combat SurveillanceInstitute of Environmental Medicine and Target Acquisition Lab

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Commander Technical Library Chemical ResearchU.S. Army Medical Research and Development Center

Institute of Chemical Defense Aberdeen Proving Ground, MDATlTN: SGRD-UV-AO 21010-5423Aberdeen Proving Ground,MD 21010-5425 Commander

U.S. Army Medical ResearchCommander Institute of Infectious DiseaseUSAMRDALC ATIN: SGRD-UIZ-CATTN: SGRD-RMS Fort Detrick, Frederick, MD 21702Fort Detrick, Frederick, MD 21702-5012

Director, BiologicalDirector Sciences DivisionWalter Reed Army Institute of Research Office of Naval ResearchWashington, DC 20307-5100 600 North Quincy Street

Arlington, VA 22217

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CommandantU.S. Army Aviation Chief, National Guard Buremiu

Logistics School ATFN: ATSQ-TDN ATlTN: NGB-ARSFort Eustis, VA 23604 Arlington Hall Station

111 South George Mason DriveHeadquarters (ATMD) Arlington, VA 22204-1382U.S. Army Training

and Doctrine Command CommanderATTN: ATBO-M U.S. Army Aviation and Troop CommandFort Monroe, VA 23651 ATTN: AMSAT-R-ES

4300 Goodfellow BouvelardIAF Liaison Officer for Safety St Louis, MO 63120-1798USAF Safety Agency/SEFF9750 Avenue G, SE U.S. Army Aviation and Troop CommandKirtland Air Force Base Library and Information Center BranchNM 87117-5671 ATTN: AMSAV-DIL

4300 Goodfellow BoulevardNaval Aerospace Medical St. Louis, MO 63120

Institute LibraryBuilding 1953, Code 03L Federal Aviation AdministrationPensacola, FL 32508-5600 Civil Aeromedical Institute

Library AAM-400ACommand Surgeon P.O. Box 25082HQ USCENTCOM (CCSG) Oklahoma City, OK 73125U.S. Central CommandMacDill Air Force Base, FL 33608 Commander

U.S. Army Medical DepartmentDirector and SchoolDirectorate of Combat Developments ATTN: LibraryATTN: ATZQ-CD Fort Sam Houston, TX 78234Building 515Fort Rucker, AL 36362 Commander

U.S. Army Institute of Surgical ResearchU.S. Air Force Institute ATITN: SGRD-USM

of Technology (AFIT/LDEE) Fort Sam Houston, TX 78234-6200Building 640, Area BWright-Patterson AAMRL/HEXAir Force Base, OH 45433 Wright-Patterson

Air Force Base, OH 45433Henry L TaylorDirector, Institute of Aviation Ali University LibraryUniversity of Illinois-Willard Airport (AUL/LSE)Savoy, IL 61874 Maxwell Air Force Base, AL 36112

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Product Manager CommanderAviation Life Support Equipment Code 3431ATTN: SFAE-AV-LSE Naval Weapons Center4300 Goodfellow Boulevard China Lake, CA 93555St. Louis, MO 63120-1798

Aeromechanics LaboratoryCommander and Director U.S. Army Research and Technical LabsUSAE Waterways Experimeimt Station Ames Research Center, M/S 215-1ATTN: CEWES-IM-MI-R, Moffett Field, CA 94035

CD Department3909 Halls Ferry Road Sixth U.S. ArmyVicksburg, MS 39180-6199 ATTN: SMA

Presidio of San Francisco, CA 94129Commanding OfficerNaval Biodynamics Laboratory CommanderP.O. Box 24907 U.S. Army Aeromedical CenterNew Orleans, LA 70189-0407 Fort Rucker, AL 36362

Assistant Commandant Strughold Aeromedical LibraryU.S. Army Field Artillery School Document Service SectionATTN: Morris Swott Technical Library 2511 Kennedy CircleFort Sill, OK 73503-0312 Brooks Air Force Base, TX 78235-5122

Mr. Peter Seib Dr. Diane DamosHuman Engineering Crew Station Department of Human FactorsBox 266 ISSM, USCWestland Helicopters Limited Los Angeles, CA 90089-0021Yeovil, Somerset BA20 2YB UK

U.S. Army White SandsU.S. Army Dugway Proving Ground Missile RangeTechnical Library, Building 5330 ATTN: STEWS-IM-STDugway, UT 84022 White Sands Missile Range, NM 88002

U.S. Army Yuma Proving Ground U.S. Army Aviation EngineeringTechnical Library Flight ActivityYuma, AZ 85364 ATITN: SAVTE-M (Tech Lib) Stop 217

Edwards Air Force Base, CA 93523-5000AFFTC Technical Library6510 TW/TSTL Ms. Sandra G. HartEdwards Air Force Base, Ames Research CenterCA 93523-5000 MS 262-3

Moffett Field, CA 94035

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Commander Italian Army Liaison OfficeUSAMRDALC Building 602ATTN: SGRD-UMZ Fort Rucker, AL 36362Fort Detrick, Frederick, MD 21702-5009

Directorate of Training DevelopmentCommander Building 502U.S. Army Health Services Command Fort Rucker, AL 36362ATTN: HSOP-SOFort Sam Houston, TX 78234-6000 Chief

USAHEL/USAAVNC Field OfficeU. S. Army Research Institute P. 0. Box 716Aviation R&D Activity Fort Rucker, AL 36362-5349AITN: PERI-IRFort Rucker, AL 36362 Commander, U.S. Army Aiation Center

and Fort RuckerCommander ATlTN: ATZQ-CGU.S. Army Safety Center Fort Rucker, AL 36362Fort Rucker, AL 36362

ChiefU.S. Army Aircraft Development Test & Evaluation Coordinating Board

Test Activity Cairns Army Air FieldATTN: STEBG-MP-P Fort Rucker, AL 36362Cairns Army Air FieldFort Rucker, AL 36362 Canadian Army Liaison Office

Building 602Commander Fort Rucker, AL 36362USAMRDALCATTN: : GRD-PLC (COL R. Gifford) German Army Liaison OfficeFort Detrck, Frederick, MD 21702 Building 602

Fort Rucker, AL 36362TRADOC Aviation LOUnit 21551, Box A-209-A French Army Liaison OfficeAPO AE 09777 USAAVNC (Building 602)

Fort Rucker, AL 36362-5021Netherlands Army Liaison OfficeBuilding 602 Australian Army Liaison OfficeFort Rucker, AL 36362 Building 602

Fort Rucker, AL 36362British Army Liaison OfficeBuilding 602 Dr. Garrison RapmundFort Rucker, AL 36362 6 Burning Tree Court

Bethesda, MD 20817

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Commandant, Royal Air Force DirectorInstitute of Aviation Medicine Army Personnel Research EstablishmentFarnborough, Hampshire GU14 6SZ UK Farnborough, Hants GU14 6SZ UK

Defense Technical Information U.S. Army Research and TechnologyCameron Station, Building 5 Laboratories (AVSCOM)Alexandra, VA 22304-6145 Propulsion Laboratory MS 302-2

NASA Lewis Research CenterCommander, U.S. Army Foreign Science Cleveland, OH 44135

and Technology CenterAIFRTA (Davis) Commander220 7th Street, NE USAMRDALCCharlottesville, VA 22901-5396 ATTN: SGRD-ZC (COL John F. Glenn)

Fort Detrick, Frederick, MD 21702-5012

CommanderApplied Technology Laboratory Dr. Eugene S. ChanningUSARTL-ATCOM 166 Baughman's LaneATTN: Library, Building 401 Frederick, MD 21702-4083Fort Eustis, VA 23604

U.S. Army Medical DepartmentCommander, U.S. Air Force and School

Development Test Center USAMRDALC Liaison101 West D Avenue, Suite 117 ATTN: HSMC-FREglin Air Force Base, FL 32542-5495 Fort Sam Houston, TX 78234

Aviation Medicine Clinic Dr. A. KornfieldTMC #22, SAAF 895 Head StreetFort Bragg, NC 28305 San Francisco, CA 94132-2813

Dr. H. Dix Christensen NVESDBio-Medical Science Building, Room 753 AMSEL-RD-NV-ASID-PSTPost Office Box 26901 (Attn: Trang Bui)Oklahoma City, OK 73190 10221 Burbeck Road

Fort Belvior, VA 22060-5806

Commander, U.S. Army MissileCommand CA Av Med

Redstone Scientific Information Center HQ DAACATTN: AMSMI-RD-CS-R Middle Wallop

/1LL Documents Stockbridge, Hants S020 8DY UKRedstone Arsenal, AL 35898

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Dr. Christine Schlichting 35th Fighter WingBehavioral Sciences Department 35th FW/SGBox 900, NAVUBASE NLON PSC 1013Groton, CT 06349-5900 APO AE 09725-2055

Aerospace Medicine Team 66th Rescue SquadronHQ ACC/SGST3 66th RQS/SG162 Dodd Boulevard, Suite 100 4345 Tyndall AvenueLangley Air Force Base, Nellis Air Force Base, NV 89191-6076VA 23665-1995

71st Rescue SquadronCommander 71st RQS/SGAviation Applied Technology Directorate 1139 Redstone RoadATTN: AMSAT-R-TV Patrick Air Force Base,Fort Eustis, VA 23604-5577 FL 32925-5000

COL Yehezkel G. Caine, MD DirectorSurgeon General, Israel Air Force Aviation Research, DevelopmentAeromedical Center Library and Engineering CenterP. O. Box 02166 I.D.F. ATTN: AMSAT-R-ZIsrael 4300 Goodfellow Boulevard

St. Louis, MO 63120-1798HO ACC/DOHP205 Dodd Boulevard, Suite 101 CommanderLangley Air Force Base, USAMRDALCVA 23665-2789 ATITN: SGRD-ZB (COL C. Fred Tyner)

Fort Detrick, Frederick, MD 21702-5012

41st Rescue Squadron41st RQS/SG Commandant940 Range Road U.S. Army Command and General Staff

Patrick Air Force Base, CollegeFL 32925-5001 ATMN: ATZL-SWS-L

Fort Levenworth, KS 66027-690048th Rescue Squadron48th RQS/SG801 Dezonia RoadHolloman Air Force Base,NM 88330-7715

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