Joint Service General Purpose Mask (JSGPM) Human 

Systems Integration (HSI) Evaluation: Comfort and 

Vision Correction Insert Stability Evaluation 

by Lamar Garrett, William H. Harper, Samson V. Ortega, 

and Timothy L. White 

ARL-TR-3900 September 2006 

Approved for public release; distribution is unlimited.
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Army Research Laboratory 

Aberdeen Proving Ground, MD 21005-5425 

ARL-TR-3900 September 2006 

Joint Service General Purpose Mask (JSGPM) Human 

Systems Integration (HSI) Evaluation: Comfort and 

Vision Correction Insert Stability Evaluation 

Lamar Garrett, William H. Harper, Samson V. Ortega, 

and Timothy L. White 

Human Research and Engineering Directorate, ARL 

Approved for public release; distribution is unlimited.
ii 

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 September 2006 

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5a. CONTRACT NUMBER

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4. TITLE AND SUBTITLE 

Joint Service General Purpose Mask (JSGPM) Human Systems Integration 

(HSI) Evaluation: Comfort and Vision Correction Insert Stability Evaluation 5c. PROGRAM ELEMENT NUMBER

5d. PROJECT NUMBER 

 62716AH70 

5e. TASK NUMBER

6. AUTHOR(S) 

 Lamar Garrett, William H. Harper, Samson V. Ortega, and Timothy L. White

 (all of ARL) 

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7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 

 U.S. Army Research Laboratory 

 Human Research and Engineering Directorate 

 Aberdeen Proving Ground, MD 21005-5425

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 REPORT NUMBER 

ARL-TR-3900

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 Approved for public release; distribution is unlimited.

13. SUPPLEMENTARY NOTES 

14. ABSTRACT 

Soldiers, first responders, and search-and-rescue personnel are among those whose job requirements include exposure to 

hazardous and toxic elements. The Joint Service General Purpose Mask (JSGPM), XM50/XM51 is being developed as the 

next generation of respirators for all ground personnel of the U.S. Armed Forces. The JSGPM, together with personal 

protective equipment, allows the operators the flexibility to tailor their protection, based on mission threat, thereby 

minimizing weight, bulk, and heat stress. This study looked at JSGPM from a systems development perspective and 

evaluated comfort, stability, donning and doffing procedures in comparison to the M40 series mask. Four configurations 

(M40 series mask with Joint Service Lightweight Integrated Suit Technology [JSLIST, jacket only], XM50 with hood, 

XM50 with JSLIST [jacket only], and the XM50 with JSLIST [jacket only] and modified mask beard) were tested. The 

analysis showed that there were no significant differences among any of the characteristics rated for the responses to the 

comfort and vision correction inserts questionnaire. The results of the comparative questionnaires showed that 94% of the 

Soldiers rated the XM50 mask as better than the M40 series mask.

15. SUBJECT TERMS

 configuration; equipment; human factors; JSGPM; mask; M40 series; NBC; XM50 

16. SECURITY CLASSIFICATION OF:

19a. NAME OF RESPONSIBLE PERSON

 Lamar Garrett 

a. REPORT 

Unclassified 

b. ABSTRACT 

Unclassified 

c. THIS PAGE 

Unclassified 

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OF ABSTRACT 

SAR 

18. NUMBER 

OF PAGES 

75 19b. TELEPHONE NUMBER (Include area code) 

 410-278-3413 

Standard Form 298 (Rev. 8/98) 

Prescribed by ANSI Std. Z39.18
iii 

Contents 

List of Figures v

List of Tables vi

Acknowledgments vii

1. Background 1

1.1 Objectives ......................................................................................................................1 

1.2 Participants.....................................................................................................................2 

1.2.1 Pre-test Orientation and Volunteer Agreement ...................................................2 

1.2.2 Health and Demographics ...................................................................................2 

1.2.3 Anthropometrics..................................................................................................3 

1.3 Equipment Configurations.............................................................................................3 

1.4 Instrumentation ..............................................................................................................6 

1.4.1 Fort Drum Light Fighter School 1-Mile Course .................................................6 

1.4.2 Questionnaires .....................................................................................................6 

1.4.3 M41 Protection Assessment Test System (PATS) ..............................................6 

1.4.4 XM50 Mask Vision Correction Inserts ...............................................................7 

2. Experimental Design 8

2.1 Independent Variables ...................................................................................................8 

2.2 Dependent Variables......................................................................................................8 

2.3 Matrix.............................................................................................................................8 

3. Procedure and Methodology 9

4. Comfort and Vision Correction Inserts Stability Evaluation 10

4.1 Clothing and Equipment and Load Configurations .....................................................10 

4.2 Questionnaires..............................................................................................................10 

4.3 Familiarization and Training........................................................................................11 

5. Participant Scenario 11

5.1 Three-Hour Wear and Vision Correction Inserts Stability Trial Evaluation ...............11 
iv 

5.2 Training........................................................................................................................12 

5.3 Three-Hour Wear Trials and Vision Correction Inserts Research Scenario................12 

5.4 Questionnaires..............................................................................................................13 

6. Data Analysis 13

6.1 Objective Measures......................................................................................................13 

6.2 Subjective Measures ....................................................................................................13 

7. Results 13

7.1 Comfort and Vision Correction Inserts Stability Evaluation.......................................13 

7.2 Mask Donning Trial Times..........................................................................................18 

8. Investigator Observations 19

9. Discussion 31

10. Conclusions 32

11. Recommendations 33

12. References 34

13. Bibliography 35

Appendix A. Volunteer Agreement Affidavit 37

Appendix B. Health and Demographics Questionnaire 43

Appendix C. Anthropometrics Measurement Summary 47

Appendix D. Vision Correction Inserts Questionnaire 51

Appendix E. Comfort (3 hour Wear Time) Trial Questionnaire 55

Appendix F. 3 hour Wear Trial Comparative Questionnaire 59

Appendix G. Demographics and Vision Summary 63

Distribution List 65 
v 

List of Figures 

Figure 1. Anthropometry measurement of Soldier head circumference........................................ 3 

Figure 2. Anthropometry measurement of Soldier bizygomatic breadth. ..................................... 3 

Figure 3. Configuration A (front view).......................................................................................... 4 

Figure 4. Configuration A (rear view). .......................................................................................... 4 

Figure 5. Configuration B (front view).......................................................................................... 5 

Figure 6. Configuration B (rear view). .......................................................................................... 5 

Figure 7. Configuration C (front view).......................................................................................... 5 

Figure 8. Configuration C (rear view). .......................................................................................... 5 

Figure 9. Configuration D (front view).......................................................................................... 6 

Figure 10. Configuration D (rear view). ........................................................................................ 6 

Figure 11. Vision correction inserts (front view)........................................................................... 7 

Figure 12. Vision correction inserts (rear view). ........................................................................... 7 

Figure 13. JSGPM (XM50 mask) with correction inserts (front view). ........................................ 7 

Figure 14. JSGPM (XM50 mask) with correction inserts (rear view)........................................... 7 

Figure 15. Broken XM50 mask temple strap clip buckle fastener. ............................................. 20 

Figure 16. Brow straps adjusted beyond recommended setting. ................................................. 20 

Figure 17. Brow straps adjusted beyond recommended setting (overhead view). ...................... 21 

Figure 18. Brow straps adjusted beyond recommended setting (left side view). ........................ 21 

Figure 19. XM51 hood material bunching up after being fitted.................................................. 22 

Figure 20. Hard to fit Soldier after 1 hour 30 minutes of wear time in Conf. C (front view). .... 23 

Figure 21. Hard to fit Soldier after 1 hour 30 minutes of wear time in Conf. C (side view)....... 23 

Figure 22. Soldier’s XM50 mask fogging while he wore vision correction inserts. ................... 24 

Figure 23. Soldier’s XM50 mask fogging while he wore vision correction inserts (side view). 24 

Figure 24. XM50 mask air flow management system not properly seated into the filter 

 housing................................................................................................................................. 25 

Figure 25. Soldier’s XM50 mask fogging because of missing interior valve disk...................... 26 

Figure 26. XM50 mask vision correction inserts were not connected to the holding pin. .......... 27 

Figure 27. Inside view of XM50 nose-cup after fluid build-up................................................... 28 

Figure 28. Inside view of XM50 mask chin cup pocket after fluid build-up............................... 28 

Figure 29. XM50 mask front module cover communication device flexed while the Soldier was 

attempting to remove the drink tube from the drink tube housing assembly....................... 28 

Figure 30. XM50 mask with modified mask beard voice amplifier push tab (bottom).............. 29 

Figure 31. XM50 mask drink tube hose assembly detached from the drink tube housing 

assembly................................................................................................................................ 30 

Figure 32. XM50 mask with two marks on the outer eye lens. ................................................... 30 
vi 

List of Tables 

Table 1. Individual equipment configurations matrix.................................................................... 8 

Table 2. Order of presentation matrix............................................................................................ 9 

Table 3. Comfort and vision correction inserts stability trial equipment load configuration...... 10 

Table 4. Research participant scenario. ....................................................................................... 11 

Table 5. Summary of results of comfort trials (3 hour wear times) questionnaire. ..................... 14 

Table 6. Summary of results of comparative questionnaire. ....................................................... 15 

Table 7. Summary of Soldiers’ comments................................................................................... 16 

Table 8. Record of mask donning trial times (seconds)............................................................... 19 

Table C-1. Summary of range, minimum, maximum, mean, standard error, and standard 

deviation for anthro-pometric measures and percentiles. ..................................................... 47 

Table C-2. Summary of anthropometric data .............................................................................. 48 

Table G-1. Demographic data summary...................................................................................... 63 

Table G-2. Vision screening summary ........................................................................................ 64 
vii 

Acknowledgments 

The authors wish to express their appreciation to all those within and outside the U.S. Army 

Research Laboratory (ARL) who shared their time and expertise in the planning and execution of 

this field experiment. 

First and foremost, we would like to thank our U.S. Army Soldiers at Fort Drum, New York, for 

their participation in this study, their interest, patience, and exceptional performance. 

We would also like to express our appreciation to Ron Carty of the Simulation Systems Branch 

of ARL’s Human Research and Engineering Directorate for his photography and videotaping 

support. 
viii 

INTENTIONALLY LEFT BLANK
1 

1. Background 

The Joint Service General Purpose Mask (JSGPM), XM50/XM51, is being developed as the 

next-generation general purpose respirator for all ground personnel of the U.S. Armed Forces. 

The JSGPM is a lightweight, protective mask system, which may be fielded in two versions 

(consisting of XM50 mask, carrier, and accessories). One version is used for field and shipboard 

operations (XM50), and the other version is used by combat vehicle crews (XM51). The JSGPM 

incorporates state-of-the-art technology to protect U.S. forces from all known threats. The mask 

components are integrated to reduce the impact on the wearer’s performance and to minimize 

equipment compatibility issues. The mask, combined with other nuclear, biological, and 

chemical (NBC) protective equipment, provides an integrated NBC protective system. The 

protective mask, together with other new and developmental personal protective equipment, 

allows the operators the flexibility to tailor their protection, based on mission threat, thereby 

minimizing weight, bulk, and heat stress. The final design of the JSGPM meets numerous 

performance specifications ranging from contaminant filtering capabilities to packaging size to 

user comfort. Unique features of the field (XM50) and combat vehicle (XM51) versions of the 

JSGPM concepts include a single, panoramic lens to minimize visual encumbrance, lower 

inspiratory (30 mm of H2O at 85l/min) and expiratory (10 mm of H2O at 85l/min) air flow 

resistances. This is a significant improvement when compared to predecessor mask systems such 

as the M40 and MCU-2/P higher inspiratory (50 mm of H2O at 85l/min) and expiratory (24 mm 

of H2O at 85l/min) air flow resistances. However, when one changes the M40/MCU2/P, C2A1 

filter canister, differences between filter lots may result in a slight change in the breathing 

resistance by ±5 mm. 

The Product Manager (PM), JSGPM, Edgewood Chemical and Biological Command, Maryland, 

requested the U.S. Army Research Laboratory’s (ARL) Human Research and Engineering 

Directorate to conduct a comfort and vision correction insert stability study and to assess other 

human factors issues associated with the JSGPM. 

1.1 Objectives 

The objectives of this study were four-fold: 

• Evaluate the comfort level with a JSGPM, with and without a modified mask beard, 

• Evaluate the stability of the interface between the JSGPM protective mask and a vision 

correction insert during wear, 

• Evaluate the war fighter’s ability to don and doff the JSGPM effectively, and 

• Compare the comfort, stability, and correct wearing of the JSGPM against the current NBC 

protective mask system, the M40 series mask. 
2 

1.2 Participants 

The 34 male participants used during this study, which was conducted at Fort Drum, New York, 

held the following military occupational specialties (MOS): 11B, 13D, 19D, 21B, 25F, 63B, 

63J, 74D, 88M, 91W, and 98C. The participants ranged in age from 19 to 38 years (mean = 24.8 

years), with 7 months to 20 years of military service (mean = 3.4 years). Twelve Soldiers elected 

not to participate in the study. One Soldier elected not to participate after completing the first 

trial. Two Soldiers were unable to participate during the last three days of this study, partly 

because of their medical profiles, and five participants did not participate on the last day of the 

trials. 

1.2.1 Pre-test Orientation and Volunteer Agreement 

Investigators assembled the Soldiers and provided an orientation about the purpose of the study 

and their participation. The Soldiers were briefed about the objectives of the study and 

procedures for each experimental condition. The Soldiers were informed how the test results 

were to be used and the benefits the military expected from this study. 

Following the pre-test orientation, the volunteer agreement affidavit (see appendix A) was 

explained and its contents verbally presented. Afterwards, time was taken to address questions 

from the Soldiers. The Soldiers were then given the volunteer agreement affidavits, which they 

read and signed if they decided to volunteer. If the Soldier chose not to participate, he was 

instructed to report back to his unit. 

1.2.2 Health and Demographics 

The volunteer Soldiers completed a health and demographics questionnaire (see appendix B) to 

document information related to their medical history and level of experience wearing 

respiratory protection equipment. The investigators asked the Soldiers if any of them had a 

medical profile or history that would jeopardize their safety if they participated in the study. 

The investigators screened Soldiers for normal or corrected-to-normal visual acuity in both eyes 

with the use of a Titmus1 2a vision tester. A Titmus 2a vision tester (Model QV-7M) was used 

to measure acuity, stereo depth, and color vision. Correction inserts were issued to Soldiers 

when unaided visual acuity in each eye was less than 20/20 for military vehicle operators, flight 

personnel, and enlisted personnel with Profile I occupational requirements and unaided binocular 

visual acuity of less than 20/40 for all other personnel (additional information regarding vision 

correction inserts is presented in Army Regulation 40-63, 1986). Vision correction inserts were 

issued to all Soldiers who required them. 

 1Titmus is a registered trademark of Titmus Optical, Inc.
3 

1.2.3 Anthropometrics 

Anthropometric measurements (see appendix C) were taken for each Soldier (see figures 1 and 2). 

Thirteen anthropometric measurements (stature, weight, bitragion coronal arc, bitragion crinion 

arc, bitragion frontal arc, bitragion subnasale arc, bitragion chin arc, bitragion submandibular arc, 

head circumference, bizygomatic breadth, head breadth, head length, and interpupillary breadth) 

were taken for each Soldier. These data are presented in appendix C. All measurements were 

made in accordance with those described in the anthropometric measurement handbook (Gordon, 

Churchill, Clauser, Bradtmiller, McConville, Tebbetts, & Walker, 1989). The measurement data 

were converted to percentile values based on data from the 1988 Army Anthropometric Survey 

(Gordon et al., 1989) to determine if the sample of Soldiers used in this study was representative 

of the user population. 

 

 Figure 1. Anthropometry measurement of Figure 2. Anthropometry measurement of 

 Soldier head circumference. Soldier bizygomatic breadth. 

1.3 Equipment Configurations 

For ease of managing the four different configurations, a letter was designated for each configuration of the XM50. The M40 series mask with Joint Service Lightweight Integrated Suit 

Technology (JSLIST, jacket only) was designated as “configuration A”; the XM50 with hood 

was designated as “configuration B”; the XM50 with JSLIST (jacket only) was designated as 

“configuration C”; and the XM50 with JSLIST (jacket only) and modified mask beard was 

designated as “configuration D”. 
4 

The XM50 is a lightweight, protective mask system incorporating state-of-the-art technology to 

protect U.S. forces from all current and future threats. The mask components were designed to 

minimize impact on the wearer and maximize its ability to interface with current and future 

service equipment and protective clothing. The design consists of a butyl-silicone blend face 

piece with a skull cap suspension system, twin conformal filters, and a panoramic urethane lens. 

The M40 series provides respiratory, eye, and face protection against chemical and biological 

agents. The mask consists of a silicone rubber face piece with an “in-turned” peripheral face seal 

and binocular rigid lens system. A face-mounted canister (gas and aerosol filter) can be worn on 

either the left or the right cheek. Microphone, hose, and canister carrier are provided for combat 

vehicle applications. 

The JSLIST overgarment is a universal, lightweight, two-piece, front-opening suit that can be 

worn as an overgarment or as a primary uniform over underwear. It has an integral hood, 

bellows-type sockets, high-waist trousers, adjustable suspenders, adjustable waistband and a 

waist-length jacket that enhances system comfort, improves system acceptance, and maximizes 

compatibility with the individual user equipment. 

The four different configurations for this study are shown in figures 3 through 10. 

 

Figure 3. Configuration A (front view). Figure 4. Configuration A (rear view). 
5 

 

Figure 5. Configuration B (front view). Figure 6. Configuration B (rear view). 

 

Figure 7. Configuration C (front view). Figure 8. Configuration C (rear view). 
6 

 

Figure 9. Configuration D (front view). Figure 10. Configuration D (rear view). 

1.4 Instrumentation 

1.4.1 Fort Drum Light Fighter School 1-Mile Course 

The light fighter school course at Fort Drum, New York, consisted of a generally flat asphalt 

surface approximately 1 mile in length. The course consisted of a starting and stopping point 

and markings along various points of the circular route. 

1.4.2 Questionnaires 

Three questionnaires (see appendices D through F) were used during this study to collect human 

factors data related to the comfort and stability of the vision correction inserts: 3-hour wear trial 

survey, comparative questionnaires, and vision correction inserts survey. 

1.4.3 M41 Protection Assessment Test System (PATS) 

The M41 PATS was used to assess the adequacy of each participant’s XM50 mask fit. The M41 

PATS is a small portable instrument designed to provide the Soldier with a simple, rapid, and 

accurate means of validating the face piece fit of his protective mask. The M41 PATS instrument 

is 240 mm x 190 mm x 140 mm in size, weighs approximately 3 lb, and is based on a miniature 

condensation nucleus counter (CNC). The CNC operates by continuously sampling and counting 

microscopic particles that occur naturally in the surrounding air. The M41 PATS measures the 
7 

concentration of these particles inside and outside the mask and, from these values, calculates a fit 

factor. The fit factor is a measure of the quality of the face seal. The M41 PATS ensures that the 

Soldier’s assigned protective mask is properly sized and fitted and has no leaks. The system aids 

in sizing and fitting of protective masks by quantitatively assessing the degree of protection 

provided by the mask once it has been donned. Investigators obtained fit factor measurements 

while volunteers completed a five-exercise routine consisting of normal breathing, deep breathing, 

side-to-side head movement, up and down head movement, and rotation of the jaw. Each of the fit 

factor exercises lasted 1 minute. 

1.4.4 XM50 Mask Vision Correction Inserts 

The present insert for XM50 mask is a single size, (see figures 11 and 12). It has a 44-mm eye 

with a 30-mm bridge and is secured by means of integral split mounting half rings with slide 

insert fasteners (see figures 13 and 14). 

 

Figure 11. Vision correction inserts (front view). Figure 12. Vision correction inserts (rear view).

 

Figure 13. JSGPM (XM50 mask) with correction Figure 14. JSGPM (XM50 mask) with correction 

 inserts (front view). inserts (rear view). 
8 

2. Experimental Design 

2.1 Independent Variables 

The independent variables for the 3–hour wear trials were the equipment configurations 

(conditions A, B, C, and D) shown in table 1. 

Table 1. Individual equipment configurations matrix. 

Configurations Equipment 

A M40 mask, with JSLIST jacket only, BDUs, combat boots, load-bearing vest (LBV), 

personal armor system for ground troops (PASGT) or modular integrated 

communications helmet (MICH) 

B JSGPM with hood, BDUs, combat boots, LBV, PASGT or MICH 

C JSGPM with JSLIST jacket only, BDUs, combat boots, LBV, PASGT or MICH 

D JSGPM with JSLIST jacket only and modified mask beard, BDUs, combat boots, 

LBV, PASGT or MICH 

Note: All configurations consist of the same equipment except for the following items: 

1. Configuration A. M40 mask with JSLIST (jacket only) 

2. Configuration B. JSGPM with hood 

3. Configuration C. JSGPM with JSLIST (jacket only) 

4. Configuration D. JSGPM with JSLIST (jacket only) and modified mask beard 

2.2 Dependent Variables 

The dependent variables were 

a. Comfort and compatibility observations. 

b. Responses to comfort and compatibility questionnaires were completed during post-action 

interview. 

c. The number of equipment failures and shortcomings for the XM50 mask. 

d. Donning and doffing times. 

2.3 Matrix 

The Soldiers wore four equipment configurations over 4 days. The presentation order was 

counterbalanced as shown in table 2. 
9 

Table 2. Order of presentation matrix. 

Test Participant 

(TP) Number 

Trial 1 Trial 2 Trial 3 Trial 4 

3 B A C D 

4 B A D C 

7 A C B D 

8 A C D B 

9 B C D A 

12 B D A C 

13 A B C D 

14 A B D C 

15 B C A D 

16 A D B C 

18 A D B C 

20 B D C A 

21 C A B D 

22 C A D B 

23 C B A D 

24 C B D A 

25 C D A B 

26 C D B A 

27 D A B C 

28 D A C B 

30 D B A C 

34 D B C A 

35 D C A B 

36 D C B A 

3. Procedure and Methodology 

The Soldiers were given a briefing about data collection procedures to be followed throughout 

the study. All participants were trained how to use and maintain the XM50, using the methods 

provided during instructor and key personnel training (IKPT). Before each evaluation trial, a 

visual inspection of the Soldiers’ equipment was performed, and each Soldier was fitted with the 

mask to ensure that all war-fighter equipment was properly donned. 

After each comfort trial, ARL experimenters and contractors from AVON Corporation2

examined the XM50 mask for any visible damage that may have occurred during the comfort 

trials. Any questions concerning the evaluation trial were addressed at that time. 

 2

Avon is widely regarded as a market leader in the design and manufacturer of high performance NBC protection 

respirators for the military, Special Forces, police, and civil defense.
10 

4. Comfort and Vision Correction Inserts Stability Evaluation 

The comfort trial consisted of a 3-hour mask wear trial. During the 3 hours of the wear trial, 

participants were divided into three groups and performed their normal military duties (e.g., 

conducted vehicle maintenance in the motor pool and 10-km road marches). A 5-minute water 

break was given every 30 minutes. After the 3-hour wear trial, participants removed and stowed 

their masks, participated in timed donning trials, and completed the applicable questionnaires 

(see appendix D). After completion of the questionnaire, an interview was conducted with all 

participants to ensure adequate understanding of all questionnaire responses and comments. All 

Soldiers completed a total of four comfort trials, one trial per equipment configuration over the 

course of 4 days. Participant comments, questionnaire responses, and investigator observations 

regarding comfort were documented throughout all evaluations. 

4.1 Clothing and Equipment and Load Configurations 

The clothing and equipment items that each Soldier wore or carried during this evaluation are 

shown in table 3. 

Table 3. Comfort and vision correction inserts stability trial equipment load configuration. 

Item Description Weight 

(lb) 

Weight 

(kg) 

 

Underclothing and socks 0.48 0.22 

Battle dress uniform 3.80 1.73 

Belt with buckle 0.44 0.20 

Boots (direct molded sole) 4.10 1.86 

PASGT helmet (medium) 3.30 1.50 

Modular lightweight load-carrying equipment (MOLLE) tactical LBV 1.56 0.71 

JSLIST (jacket only) 2.99 1.36 

M40 series mask with carrier 4.16 1.89 

JSGPM (XM50 mask) with carrier 2.96 1.34 

JSGPM hood 0.41 0.19 

Accessory pack 2.11 0.96 

Canteen with cover, and 1 quart of water (two each) 6.60 3.00 

Individual first aid kit 0.17 0.08 

 

Total M40 Series Mask load Configuration A 

Total JSGPM with hood load Configuration B 

Total JSGPM with JSLIST load Configuration C 

Total JSGPM with JSLIST and modified beard load Configuration D 

27.60 

26.81 

28.51 

28.51 

12.55 

12.19 

12.96 

12.96 

4.2 Questionnaires 

Questionnaires were designed to elicit Soldiers’ opinions about their experiences in wearing the 

M40 series and JSGPM mask systems. The questionnaires were designed to enable Soldiers to 
11 

rate the system on a 6-point scale ranging from “much better” to “much worse” (in which much 

better = 6, better = 5, slightly better = 4, slightly worse = 3, worse = 2, and much worse = 1). 

Questionnaires were given to each Soldier to complete after each daily trial. Soldiers rated 

features about each mask system pertaining to comfort, compatibility, and durability. A 

comparative questionnaire was administered at the completion of the study to rate the M40 

against the XM50. Sample questionnaires are shown in appendices D through F. 

4.3 Familiarization and Training 

During the first day, the Soldiers were screened for visual acuity, were issued and properly fitted 

with an XM50 and an M40 series mask, and had anthropometric measurements taken. The 

Soldiers were given a demonstration how to don and doff both masks properly and safely and 

were taught how to maintain both masks during IKPT. In addition, the Soldiers practiced the 

donning and doffing procedures until they were comfortable with them. They were then trained 

how to complete all the evaluation questionnaires. The training and familiarization took 2 days. 

5. Participant Scenario 

Four configurations were examined during this study. Each system was worn by the Soldiers on 

the light fighter school course during this study. The daily scenario that was used to conduct the 

comfort and vision correction inserts stability study is shown in table 4. This scenario was 

repeated daily for 4 days. The comfort wear trial times for each Soldier and any human factors 

and compatibility issues observed were recorded. 

Table 4. Research participant scenario. 

a. Soldiers arrived at test site in the morning. 

b. Soldiers were briefed about the day’s events, received equipment training, and were issued equipment. 

c. Soldiers conducted a series of donning trials and donned individual equipment (i.e., XM50 mask, vision 

correction, etc.) and prepared to conduct the equipment configuration trial. 

d. Soldiers performed a 3-hour wear trial, conducted timed donning trials, sanitized mask after use, and completed 

questionnaires. Experimenter(s) inspected all equipment. Shortcomings or failures observed by Soldiers or 

experimenter(s) were documented. 

e. Soldiers took a 5-minute water break every 30 minutes during the 3-hour wear trial. 

f. Soldiers completed comparative questionnaires after post action interview. 

5.1 Three-Hour Wear and Vision Correction Inserts Stability Trial Evaluation 

The M40 series mask, XM50 mask, and vision correction inserts were evaluated during the 3-

hour wear trials. Separate training and research trials were conducted for each mask 

configuration. 
12 

5.2 Training 

A New Equipment Training Team (NETT) from Sobran Incorporated trained the Soldiers in the 

procedures, proper use, and maintenance of the XM50 mask system and various components. 

Training took about approximately 4 hours. 

The Soldiers were fitted with a JSLIST overgarment jacket and donned the XM50 mask carrier, 

placing it in its predetermined operational location. The carrier contained the mask and all other 

items specified in the operator’s card. The Soldiers practiced the donning procedures, including 

removal of the mask from the mask carrier, until they were comfortable with the operating 

procedures. The procedures required for donning and doffing the XM51 NBC protective hood 

and the JSLIST overgarment with hood were explained in detail, were demonstrated, and were 

practiced. 

Once the Soldiers were comfortable with donning and doffing the XM50 mask, they performed a 

timed donning trial at the command of “gas”. The standard for donning a protective mask is 9 

seconds or less. This includes clearing and ensuring that the mask was properly sealed. Once 

the mask had been donned, Soldiers continued to don the appropriate NBC protective hood. 

Comfort trials were conducted in all test configurations. Experimenters observed the donning 

procedures and recorded donning trial times. Following the trials, the M41 PATS was used to 

determine the fit factor of randomly selected masks. After each trial, Soldiers removed and 

cleaned their individual masks before the next use. 

5.3 Three-Hour Wear Trials and Vision Correction Inserts Research Scenario 

The day after completing the training scenario, each Soldier was provided a respiratory 

protective mask (i.e., XM50 or M40 series) and protective equipment (i.e., JSLIST or XM51 

hood) in accordance with the equipment configuration matrix. The Soldiers completed one trial 

per condition over the course of four days, as listed in table 3 of the individual equipment 

configuration matrix. The Soldiers performed their normal military duty activities throughout 

the duration of the trials. After each trial was completed, the research participant was asked to 

complete the 3-hour wear trial questionnaire, 3-hour comparative questionnaire, and if 

applicable, the vision correction inserts questionnaires shown in appendices D through F. 

Participants had at least a 5-minute water break every 30 minutes during the trials. Research 

participants completed no more than one trial per equipment configuration each day during the 

evaluation. Wet bulb globe temperature (WBGT), as well as other applicable weather data, were 

recorded before each trial. 

The Soldiers received a briefing about the comfort trials and vision correction inserts scenario. 

This scenario was repeated over the course of 4 days. Investigators recorded the order in which 

Soldiers completed the trials and any human factors and compatibility issues they observed. 
13 

5.4 Questionnaires 

Questionnaires were designed to elicit Soldiers’ opinions about their experiences using the 

XM50 mask, compared to their current mask system (M40). The questionnaires were designed 

to enable Soldiers to rate the system on a 6-point rating scale. Questionnaires were given to each 

Soldier to complete after each daily trial. Additionally, a comparative questionnaire was given to 

each Soldier at the completion of the study. Features about each system pertaining to comfort, 

vision correction inserts stability, and equipment compatibility were rated. Sample 

questionnaires are shown in appendices D through F. 

6. Data Analysis 

6.1 Objective Measures 

A chronology of the failures and shortcomings observed during the 3-hour comfort wear trial, 

vision correction inserts stability, mask donning times exercises, and summarized lists for any 

other compatibility and human factors problems observed is reported. Photographs and video 

footage of equipment damage and human factors issues were taken as necessary. 

An analysis of variance (ANOVA) was conducted on the mask donning trial completion times, 

as a function of configuration. Means and standard deviations for the all the conditions are 

provided. 

6.2 Subjective Measures 

Questionnaire data were collated and used to compute descriptive statistics (means and standard 

deviations) for each of the configurations, except for the comparative questionnaire. 

7. Results 

7.1 Comfort and Vision Correction Inserts Stability Evaluation 

The linear mixed model analyses showed that there were no significant differences between any 

of the characteristics rated for the responses to the comfort and vision correction inserts questions. 

The mean responses for the comfort trials (3-hour wear time) with each of the configurations are 

shown in table 5 and a comparative questionnaire with mean responses is shown in table 6. 
14 

Table 5. Summary of results of comfort trials (3 hour wear times) questionnaire. 

Mean (Standard Error) 

Characteristics rated Conf. A Conf. B Conf. C Conf. D 

Q1 The mask around the eyes was 4.56 

(0.22) 

5.09 

(0.21) 

5.26 

(0.21) 

5.26 

(0.21) 

Q2 The mask periphery (around the combined contact points of 

the head, temples cheek and chin) was

3.33 

(0.31) 

4.47 

(0.30) 

4.65 

(0.30) 

5.05 

(0.30) 

Q3 The mask’s nosecup was 3.72 

(0.29) 

4.82 

(0.28) 

5.01 

(0.27) 

4.74 

(0.28) 

Q4 The mask’s head harness was 4.12 

(0.27) 

4.99 

(0.27) 

4.52 

(0.26) 

5.20 

(0.27) 

Q5 The mask around the throat was 3.80 

(0.30) 

4.89 

(0.29) 

4.45 

(0.29) 

4.21 

(0.29) 

Q6 The mask around the neck area was 3.93 

(0.25) 

5.14 

(0.24) 

4.75 

(0.24) 

4.47 

(0.24) 

Q7 The mask at your chin was 3.50 

(0.22) 

5.09 

(0.21) 

4.78 

(0.21) 

5.32 

(0.21) 

Q8 The mask at your forehead was 4.33 

(0.29) 

4.42 

(0.28) 

4.50 

(0.28) 

4.94 

(0.28) 

Q9 The mask overall was 3.54 

(0.25) 

4.93 

(0.25) 

4.86 

(0.24) 

5.03 

(0.25) 

Q10 The weight of the mask was 3.79 

(0.22) 

4.97 

(0.21) 

5.39 

(0.21) 

5.43 

(0.21) 

Q11 The thermal conditions of your face inside the mask were 3.53 

(0.30) 

4.36 

(0.29) 

4.56 

(0.28) 

4.84 

(0.29) 

Q12 The weight of the mask and helmet combined was 4.70 

(0.31) 

4.59 

(0.30) 

5.11 

(0.30) 

4.42 

(0.30) 

Q13 Wearing the mask carrier was 3.95 

(0.28) 

4.82 

(0.28) 

4.55 

(0.27) 

5.10 

(0.28) 

Legend: 6 = very comfortable, 5 = comfortable, 4 = slightly comfortable, 3 = slightly uncomfortable, 2 = uncomfortable, 1 = 

very uncomfortable 

Q14 Inhaling through the mask while performing this trial was 3.70 

(0.19) 

5.30 

(0.19) 

5.24 

(0.18) 

5.67 

(0.19) 

Q15 Exhaling through the mask while performing this trial was 4.05 

(0.16) 

5.52 

(0.16) 

5.59 

(0.15) 

5.62 

(0.16) 

 6 = very easy, 5 = easy, 4 = slightly easier, 3 = slightly difficult, 2 = difficult, 1 = very difficult 

Q16 The fit of the mask was 4.48 

(0.18) 

5.11 

(0.17) 

5.43 

(0.17) 

5.43 

(0.17) 

Each equipment configuration was worn during the 3-hour wear comfort trial evaluation a total 

of 4 times by the 21 Soldiers. After each comfort trial, ARL experimenters and contractors from 

AVON Corporation inspected the XM50 mask for any visible damage that may have occurred 

during the comfort trials. There was some visible damage (module cover communication device 

flex) that occurred on the XM50 mask configurations. 

The comparative questionnaire administered at the completion of the study solicited subjective 

opinions about the M40 versus the XM50 mask conditions from the 16 Soldiers, on a rating scale 

ranging from 6 to 1 (i.e., 6 = much better, 5 = better, 4 = slightly better, 3 = slightly worse, 

2 = worse, 1 = much worse). In terms of the results, 15 of 16 questions asked of Soldiers were 

answered in favor of XM50 versus M40, with rating between 5 and 6. However, it was noted 
15 

that a number of Soldiers rated the XM50 slightly worse than the M40 when asked to compare 

“accidentally detaching the XM50/51 filter during filter change-out”. A summary of the results 

of the comparative questionnaire by research participants is shown in table 6. Because this 

survey was administered to Soldiers only once at the end of the study, after they had worn all 

configurations, no comparisons could be made across the four conditions. 

Table 6. Summary of results of comparative questionnaire. 

Characteristics rated Mean Std 

Error 

Q1 Compared to your current mask system, the comfort of the XM50/51 after 3 hours 

of wear was

5.94 0.06 

Q2 Compared to your current mask system, the comfort of the XM50/51 when worn 

with mission-oriented protective posture (MOPP) gear and helmet was

5.25 0.27 

Q3 Compared to your current mask system, XM50/51 breathing resistance during 

inhalation was

5.94 0.06 

Q4 Compared to your current mask system, XM50/51 breathing resistance during 

exhalation was

5.81 0.10 

Q5 Compared to your current mask system, the fit of the XM50/51 was 5.56 0.18 

Q6 Compared to your current mask system, XM50/51 your field of view was 5.94 0.06 

Q7 Compared to your current mask carrier, the XM50/51 modular two bag carrier 

system was

5.19 0.26 

 Std Error = Standard Error 

 Legend: 6 = much better, 5 = better, 4 = slightly better, 3 = slightly worse, 2 = worse, 1 = much worse 

Q8 Compared to your current mask system, removing the XM50/51 air deflectors 

from the mask was

5.81 0.10 

Q9 Compared to your current mask system, installing the XM50/51 air deflectors 

from the mask was

5.69 0.25 

Q10 Compared to your current mask system, removing the XM50/51 inhalation valve 

from the filter mount was

5.44 0.20 

Q11 Compared to your current mask system, installing the XM50/51 inhalation valve 

from the filter mount was

5.44 0.18 

Q12 Compared to your current mask system, removing the XM50/51 self sealing 

valve from the filter mount was

5.75 0.11 

Q13 Installing the XM 50/51 self sealing valve from the filter mount was 5.56 0.26 

6 = very easy, 5 = easy, 4 = slightly easier, 3 = slightly difficult, 2 = difficult, 1 = very difficult 

Q14 Having filter alignment marks on the XM50/51 during filter change-out was 5.06 0.34 

 6 = very useful, 5 = useful, 4 = slightly useful, 3 = slightly useless, 2 = useless, 1 = very useless 

Q15 Accidentally detaching the XM50/51 filter during filter change-out was 2.94 0.38 

Q16 Accidentally detaching the XM50/51 self sealing valve from the filter mount 

during filter change-out was

5.31 0.27 

6 = very common, 5 = common, 4 = slightly common, 3 = slightly uncommon, 2 = uncommon, 1 = very uncommon 

A summary of the Soldiers’ comments (verbatim) regarding their experience with the XM50 

mask during the comfort and vision correction inserts stability trials is shown in table 7. 
16 

Table 7. Summary of Soldiers’ comments. 

Research 

Participant 

Number

Comments 

Configuration A (M40 mask with JSLIST) 

3 I experienced more breathing resistance while wearing the M40 series mask and some fogging 

did occur during the trial. I was experiencing a pressure on the outer portion of my head that 

was really uncomfortable. 

4 No comments. 

7 The M40 mask was very uncomfortable. It was difficult to breathe in. 

9 No comments. 

12 Complained of hot spot on the forehead and tightness across the forehead. 

13 While wearing the PASGT helmet, it pushed down on the front of the mask and made the 

helmet unstable. Need to find a way to stabilize helmet when I’m wearing the mask. JSLIST 

was bunching up around the neck area, causing discomfort. 

14 No comments. 

15 No comments. 

16 No comments. 

18 No comments. 

20 

After wearing the XM50 mask during the previous three trials, I no longer like the M40 series 

mask. The nosecup is hard and uncomfortable in the M40 series mask and the drink tube is 

irritable because it either pushes against my lip or must be kept in my mouth. The XM50 drink 

system is easier to use and is more maneuverable and the breathing resistance is much better in 

the XM50 mask than the M40 series mask. 

21 

The M40 mask is not good. I can hear myself breathing through the mask filter and my 

breathing does not feel natural and the mask was causing a headache around the top edge of the 

mask. While pulling the drink tube out of the drink tube housing, it caused me to break the 

mask seal. 

22 No comments. 

24 No comments. 

25 Experiencing hot spot on the top of his head and the temple straps were pressing against the 

side of his head. 

26 No comments. 

27 Complained of a headache near the top of the head. 

28 No comments. 

30 No comments. 

34 Mask began to fog up after 30 minutes of wear time. 

35 No comments. 

36 No comments. 

Configuration B (XM50 mask with hood) 

3 No comments. 

4 No comments. 

7 No comments. 

9 Stated that the nose cup was pushing down on his nostrils. 

12 No comments. 

13 No comments. 

14 The XM50 mask seals well. 

15 No comments. 

16 I experienced hot spots as a result of the mask buckles, around the cheek bones and on top of 

my head. The sunglass outserts clip did not seat properly in the slot on the left side of my 

mask. Felt pressure near the temple area and a hot spot near the brow strap area. 

18 No comments. 

20 

The canteen top unsnapped too easily; however, the drinking system was generally better than 

the previous systems. The system allows me to drink more water in a shorter duration of time. 

The hood material was slippery and more difficult to grasp during the donning trials and this 

was affecting my donning trial time. Finally, the Soldier acknowledged that the breathing 
17 

resistance was much better with JSGPM and stated that he did not sweat as much in this 

system, compared with the current mask system. 

21 No comments. 

22 Experienced a hot spot as a result of the head harness. 

24 No comments. 

25 No comments. 

26 No comments. 

27 His canteen assembly coupler interior sleeve assembly was dislodged while attempting to drink 

water from the canteen. 

28 No comments. 

30 The PASGT helmet was pushing down on the front of the mask and causing pressure on the 

forehead. 

34 The XM50 mask felt like it was pushing into his jaw and the back of his jaw was becoming 

sore as a result. He did not notice this when he wore the modified version of the XM50 mask. 

35 No comments. 

36 No comments. 

Configuration C (XM50 mask with JSLIST) 

3 The JSLIST was pushing the mask beard down into his neck (Adam’s apple). His buddy 

repositioned the JSLIST and the problem was resolved 

4 No comments. 

7 The M40 mask was very uncomfortable. It was difficult to breathe in. 

9 He had a strange feeling around his neck and Adam’s apple while wearing the JSLIST. 

12 No comments. 

13 While he wore the PASGT helmet, it pushed down on the front of the mask and made the 

helmet unstable. Need to find a way to stabilize helmet when he wears mask. 

14 No comments. 

15 No comments. 

16 I experienced hot spots as a result of the mask buckles, around the cheek bones and on top of 

my head. The sunglass outserts clip did not seat properly in the slot on the left side of my 

mask. The participant stated that he was not issued a PASGT or MICH and that one was not 

available for this trial. 

18 

The participant also stated that the thigh strap on the mask carrier was much better than the 

thigh strap on the M40 series mask carrier. This carrier is more comfortable, more stable, and 

the strap was hardly noticeable during the wear trial. 

20 No comments. 

21 He was experiencing a hot spot near the brow strap area. 

22 No comments. 

24 

The JSLIST felt like it was bunching up around the throat and he was experiencing pressure at 

the very top of the forehead as a result of front portion of the mask. He thinks the problem 

resulted from a combination of the PASGT helmet and the XM50 mask. 

25 No comments. 

26 No comments. 

27 No comments. 

28 No comments. 

30 No comments. 

34 The mask was hurting his jaw. 

35 No comments. 

36 No comments. 

Configuration D (XM50 mask with JSLIST and modified mask beard) 

3 No comments. 

4 No comments. 

7 No comments. 

9 My canteen assembly coupler interior sleeve assembly was dislodged while attempting to drink 

water from the canteen and I experienced hot spots in the front and back of head. 

12 No comments. 

13 No comments. 
18 

14 No comments. 

15 No comments. 

16 A puddle of water was forming in the chin cup pocket and he tried leaning forward and blowing 

the water out, but the water began to build up in the bottom lip of the mask chin cup pocket. 

18 No comments. 

20 

The push tab, located on the bottom of the voice amplifier, made it difficult to remove the drink 

tube from the drink tube housing assembly. The voice projection unit (VPU) makes it difficult 

to fully uncoil the drink tube from the drink tube housing assembly without removing the VPU. 

21 No comments. 

22 No comments. 

24 No comments. 

25 Was experiencing a mild headache near the brow strap area. 

26 No comments. 

27 No comments. 

28 

The interior nosecup did not feel like it was properly sealed around the interior filter housing 

unit after being emplaced following mask reassembly. The attachment feels flimsy and not real 

sturdy and the ring portion of the nosecup does not seem to fit the filter housing well because it 

seemed to be stretched. 

30 The PASGT helmet tends to press down on the XM50 mask, causing discomfort. 

34 

His breathing was restricted because the nose cup was tight, pinching his nostrils partially shut, 

and pushing down on his nostrils. Additionally, the Soldier stated, “If the nose cup sat higher 

in the mask, my breathing would not be restricted. It was easier to breathe when the nose cup is 

lifted slightly and sun lens outserts were great.” 

35 Complained of a headache after 20 minutes from the start of the donning trial. 

36 Stated that his drinking tube disconnected from exterior mask face piece housing assembly. 

7.2 Mask Donning Trial Times 

Each day following the comfort trial (3-hour wear time) Soldiers completed three practice trials 

before conducting the actual mask donning trial. The results of the mask donning trial times by 

research participant, each trial, and configuration are shown in table 8. A linear mixed model 

analysis was conducted on the mask donning trial completion times. The linear mixed model 

analyses showed that there were no significant differences (F = 51.432, p = 0.345) between the 

XM50 or M40 series mask configurations. The vision correction inserts questionnaire sample 

size was too small to conduct statistical analyses (N = 6). 
19 

Table 8. Record of mask donning trial times (seconds). 

Research 

Participant Conf. A Conf. B Conf. C Conf. D 

3 9.94 7.9 7.41 11.81 

4 6.51 7 

7 5.03 7.22 6.65 6.97 

9 10.04 12 8.35 9.78 

12 5.5 7.02 7.28 6.6 

13 

14 7.44 6.5 7.25 6.1 

15 7.9 10.5 6.59 5.57 

16 7.64 7.19 8.95 7.03 

18 8.5 7.34 7.87 7.78 

20 10.2 6.59 7.07 7.79 

21 11.43 7.25 8.09 7.85 

22 5.06 6.53 7.25 

24 4.85 7.37 7.14 6.28 

25 10.79 16.82 4.75 

26 6.32 7.12 6 6.13 

27 7.17 7.34 7.16 7 

28 7.87 5.75 4.84 6.54 

30 7.97 6.28 4.81 7.06 

34 7.79 11.15 8.22 8.17 

35 12.65 13.53 11.85 8.47 

36 8.81 6.28 8.31 

Means 8.07 7.86 7.73 7.26 

Std. Dev. 2.12 2.15 2.55 1.62 

A = M40 mask with JSLIST (jacket only) 

B = JSGPM with hood 

C = JSGPM with JSLIST (jacket only) 

D = JSGPM with JSLIST (jacket only) and modified mask beard 

8. Investigator Observations 

Since there were not enough individual protective masks to issue to each Soldier, investigators 

decided to distribute the masks based on the configuration matrix throughout the duration of the 

trial. This was done on the first day of the trials. 

Several problems were noted regarding the PASGT helmet. During disassembly of the XM50 

after the 3-hour wear trials, investigators noticed that the temple strap mask harness clip buckle 

(left size) broke before mask fitting (see figure 15). It was also noted that a relatively small 

number of Soldiers were unable to localize sound when they wore the PASGT helmet. However, 

after switching to a MICH, the Soldiers were able to successfully localize sound. Because of the 

shortness of the brow straps, the mask was adjusted beyond the recommended factory setting to 

accommodate participant 9 in Configuration B during the initial mask fitting exercise (see 

figures 16 through 18). 
20 

Figure 15. Broken XM50 mask temple strap clip buckle fastener. 

Figure 16. Brow straps adjusted beyond recommended setting. 
21 

Figure 17. Brow straps adjusted beyond recommended setting (overhead view). 

Figure 18. Brow straps adjusted beyond recommended setting (left side view). 
22 

When the Soldier attempted to loop the brow strap through the XM51 hood, an unnatural pull 

was created and the material bunched up (see figure 19). To correct the problem, the brow straps 

were removed from the XM51 hood loops and readjusted to correct the comfort issue. This 

adjustment appeared to have corrected the problem. After anthropometry measurements for 

participant 9 (Configuration B) were checked, it was noted that the Soldier was beyond the 98th 

percentile anthropometry measure for several head (i.e., head circumference, head length, etc.) 

and facial (i.e., bitragion chin arc) measurements. 

Figure 19. XM51 hood material bunching up after being fitted. 

During the comfort trials, it was obvious that several of the participants experienced problems. 

For participant 16 (Configuration B), the sunglass outserts clip was not seated properly in the slot 

on the left side of the mask. The Soldier was initially fitted with a large XM50 mask using the 

M41 PATS; however, the location of the eyes and the nose cup indicated that the mask was too 

large. It was determined that the Soldier required a medium mask. Participant 9 was identified 

as “hard to fit” after informing the researchers that a medium size mask beard felt very 

uncomfortable and the nose cup interfered with his field of view. The Soldier was resized and 

reissued a large XM50 mask before the start of the first trial. Within 10 minutes after the first 

trial began and 30 minutes after the initial observation, it was clearly visible that the Soldier had 

an issue with fogging. The probable causes of this issue were (a) the Soldier was hard to fit with 

a mask and (b) the proximity of the relief distance between the mask lens and the forehead, 

which restricted the amount of turbulence (air flow) within the interior of the mask. In addition 
23 

to the fogging issue, the Soldier stated that he was experiencing a headache. The Soldier’s mask 

(Configuration C) was removed after 1 hour and 30 minutes of participation as a safety 

precaution (see figures 20 and 21). 

 

Figure 20. Hard to fit Soldier after 1 hour Figure 21. Hard to fit Soldier after 1 hour 

 30 minutes of wear time in 30 minutes of wear time in 

 Conf. C (front view). Conf. C (side view).

Participant 13’s (Configuration C) vision correction inserts were fogging while he breathed 

through the nose. However, while he breathed through his mouth, the vision correction inserts 

did not fog up as much (see figures 22 though 23). The experimenters removed the participant’s 

mask to troubleshoot the problem. It was observed that the left side pop valve was missing. The 

valve was replaced and the Soldier’s mask still fogged up. The Soldier was instructed to remove 

the mask again. 

The experimenters observed that the right side of the mask air flow management system of the 

non-modified mask was not properly seated onto the interior filter housing (see figure 24). After 

2 hours 30 minutes of wear time, the Soldier still experienced fogging inside the XM50 mask. 

Therefore, the corrections made earlier did not resolve the fogging issue. It was noted that the 

fogging issue was now on the opposite side (right side lens). The Soldier was instructed to 

remove the mask and the vision correction inserts. The participant donned the mask and walked 

around the test area to determine if fogging would still occur. The Soldier informed the 

experimenter that the fogging problem was no longer occurring once the vision correction inserts 

were removed. 
24 

Figure 22. Soldier’s XM50 mask fogging while he wore vision correction inserts. 

Figure 23. Soldier’s XM50 mask fogging while he wore vision correction inserts (side view). 
25 

Figure 24. XM50 mask air flow management system not properly seated into the filter housing. 

Participant 13’s (Configuration C) XM50 mask began to fog up (see figure 25) almost 

immediately after he donned the mask. After the Soldier was instructed to clear and reseal the 

mask, he was instructed to remove the mask. After a closer observation by the researchers, it 

became obvious that the interior valve disks were missing. After the valve disks were installed, 

the Soldier donned the mask onto his face and experienced no further problems with fogging. 

Participant 20’s (Configuration C) XM50 mask was making a whistling sound. This was 

because of an incorrectly emplaced pop valve in the outlet valve housing assembly. The valve 

was replaced and the Soldier experienced no further problems. 

Participant 21 (Configuration C) experienced a hot spot near the brow strap area. The Soldier 

was refitted with the mask because the reflex seal on the inside of the mask was bent as a result 

of the positioning of the brow strap. The brow straps were removed from the hood to prevent the 

reflex seal from pinching or bending the XM50, causing the Soldier discomfort. The mask was 

refitted and no further problems occurred. 
26 

Figure 25. Soldier’s XM50 mask fogging because of missing interior valve disk. 

Participant 22’s (Configuration C) XM50 mask began to fog up approximately 15 minutes after 

he donned it. Additionally, the Soldier wore vision correction inserts, but it is unclear if this 

contributed to the fogging problem. The fogging issue was corrected after the Soldier removed 

and re-donned the mask. 

Participant 25’s (Configuration B) XM50 mask began to fog up 2 hours into the comfort trial. 

The Soldier informed the experimenters that he was breathing through his nose when the fogging 

began. After closer observation by the researchers, it became obvious that the interior mask 

nosecup was not properly sealing against the bridge of the nose. This allowed air turbulence to 

flow up and across the lens, causing the lens to fog up. The experimenters instructed the Soldier 

to remove his mask. The Soldier was refitted, cleared, and sealed the XM50 mask. The Soldier 

experienced no further problems. 

Participant 28 (Configuration D) informed the experimenters that the interior nosecup did not 

feel like it was properly sealed around the interior filter housing unit during reassembly of the 

XM50 mask. He reported that the attachment felt flimsy and not sturdy. The ring portion of the 

nosecup did not seem to fit around the filter housing well, possibly because of stretching. The 

vision correction insert frame pressed on his forehead. The experimenters observed that the 

vision correction inserts were not connected to the holding pin, located on the interior of the 

XM50 mask (see figure 26). The vision correction inserts were adjusted (lowered two notches) 

to correct the problem. 
27 

Figure 26. XM50 mask vision correction inserts were not connected to the holding pin. 

Participant 35 (Configuration D) informed the experimenters that a puddle of water was forming 

in the XM50 mask chin cup pocket. The Soldier tried leaning forward and blowing out, but the 

water had puddled at the bottom lip of the mask chin cup pocket. The water was spattering up 

into his face when he breathed hard. The Soldier was instructed to remove the mask to diagnose 

the issue. When the experimenters and contractors examined the mask, they noticed there was 

very little water in the chin cup pocket. The water had not been draining from the hole in the 

chin cup pocket (see figures 27 and 28). 

The front module cover communication device flexed when the participant attempted to remove 

his drinking tube from the drinking tube housing (see figure 29). The push tab on the bottom of 

the voice amplifier made it difficult to remove the drink tube from the drink tube housing 

assembly (see figure 30). The Soldier (Configuration D) demonstrated that the location of the 

bottom push tab on the VPU made it difficult to fully uncoil the drink tube from the drink tube 

housing assembly without removing the VPU. The sound of the VPU was heard from a distance 

not exceeding 5 meters; however, the sound quality was clear and understandable. 
28 

 

Figure 27. Inside view of XM50 nose-cup after fluid Figure 28. Inside view of XM50 mask chin cup

 build-up. pocket after fluid build-up.

Figure 29. XM50 mask front module cover communication device flexed while the Soldier was attempting 

to remove the drink tube from the drink tube housing assembly. 
29 

Figure 30. XM50 mask with modified mask beard voice amplifier 

push tab (bottom). 

After mask sanitation, one of the XM50 mask drink tube hose assemblies detached from the 

drink tube housing assembly (see figure 31). 

Mask serial number KO50513 (Configuration D) had two marks on the outer eye lens. We were 

not certain what had caused this (see figure 32). 
30 

Figure 31. XM50 mask drink tube hose assembly detached from the drink tube housing assembly. 

Figure 32. XM50 mask with two marks on the outer eye lens. 
31 

9. Discussion 

As indicated by the responses to the comparative questionnaires, table 6 showed (in general) that 

Soldiers rated the XM50 mask as better than the M40 series mask in 15 of the 16 questions. A 

review of the comfort (3-hour wear time) and comparative questionnaires comments indicates 

that all the Soldiers had a much higher perception of the XM50 mask, when compared to the 

M40 series mask. Most Soldiers liked the comfort and durability of the XM50 mask. They also 

liked the drinking system and accessory pack of configurations C and D and stated that this mask 

is a vast improvement over the M40 mask series mask system. The Soldiers said they believe 

that the XM50 mask improvements will greatly enhance survivability. 

Comfort (3-hour wear time) and vision correction inserts stability was investigated through 

questionnaires, the Soldiers’ comments, and experimenters’ observation. At the completion of 

the study, a comparative questionnaire was administered to the Soldiers to provide their opinions 

of the M40 series and XM50 mask systems. There are no criteria for the comfort trial (3-hour 

wear time) other than existing published reports (Caretti & Barker, 2002). The requirement for 

mask donning is 9 seconds or less to clear and seal the protective mask, and this requirement was 

met by a majority of Soldiers. The vision correction inserts questionnaire did not have enough 

participants to determine trends; therefore, the analyses could not be addressed since the sample 

size was too small. Note that a number of Soldiers chose not to participate in this study. 

There were a small number of fogging issues related to the XM50 non-modified and modified 

masks. One possible cause of these issues was attributable to the proximity of the relief distance 

between the mask lens and the forehead, which restricted the amount of turbulence (air flow) 

within the interior of the mask. One common issue that continued to surface was the number of 

complaints of “hot spots,” which in most cases, was also associated with headaches or 

discomfort. Finally, there were times during the trial when the equipment was damaged or it 

malfunctioned (see figures 15 and 29). This often occurred during mask fitting or reassembly of 

the XM50 mask. However, since the XM50 was a prototype mask, equipment malfunction and 

damage was quite common and generally surfaced during field testing. 

Overall, Soldiers rated all the mask characteristics to be significantly better for the XM50 

configurations than for the baseline M40 series mask system, except for the fogging issues 

during the comfort trials (figures 22 and 23). This shows that the Soldiers, in general, favored 

the XM50 configurations since most of the ratings were slightly higher than the M40 series 

mask. A similar trend can be seen for the comparative questionnaire, where Soldiers’ ratings of 

the XM50 configurations were also in the higher categories (table 9). 
32 

As shown in tables C-1 and C-2, there is a wide range of values and percentiles for each of the 

anthropometric measures obtained from the Soldiers. This shows large anthropometric 

variability in the Soldiers who participated in this study and the facial and head measurement 

generally included Soldiers below the 5th percentile male values to above the 95th percentile 

male values. 

The fact that there were no female participants in this group of Soldiers is a shortcoming of this 

study, and it forces the designer to make modifications based solely on the opinion and 

performance of male Soldiers. Therefore, the authors strongly encourage additional tests to 

gather unbiased opinions of the XM50 mask from female participants. 

With respect to the comfort trials of the XM50 configurations, the results indicated positive 

ratings of 5.52, 5.59, and 5.67 for the B, C, and D configurations, respectively. This indicates 

that Soldiers, in general, highly rated the comfort of the XM50 masks, based on their experience 

in this test. 

10. Conclusions 

1. The 10-km road march did not affect the integrity of XM50 mask configurations. 

2. The integration between the JSLIST and PASGT helmet with the XM50 mask slightly 

affected the integrity of XM50 mask configurations. This was evidenced by the number of 

comments made about the XM50 mask configurations by Soldiers after the 3-hour wear trial 

over the course of 4 days. 

3. There were no significant differences for the donning trial completion times between any of 

the configurations. 

4. Most of the Soldiers positively rated the comfort and durability of the XM50 mask while they 

acknowledged that the breathing resistance was much better with the XM50 mask configurations 

than the M40 series mask. 

5. The XM50 mask configurations’ drinking system was positively rated by the majority of 

Soldiers. 

6. There were a number of comfort issues as a result of hot spots; most were related to the brow 

and temple straps (head and forehead) with the XM50 mask configurations. 

7. A small number of fogging issues were observed that were a direct or indirect result of 

restricted air flow with the modified XM50 mask configuration. 
33 

8. The vision correction inserts’ stability was positively rated by the majority of users; however, 

a number of fogging issues occurred when the vision correction inserts were worn with the 

XM50 modified mask. 

9. The location and length of the thigh strap on the XM50 mask carrier were an improvement 

over the M40 series mask carrier. Overall, the accessory pack and XM50 mask carrier received 

positive ratings. 

10. There were a number of comfort and compatibility issues with M40 series mask 

configuration. 

11. Overall, user acceptance of the XM50 mask configurations was excellent for both comfort 

and durability performance. 

11. Recommendations 

1. Move or reposition the VPU push tab (located on the bottom) off to the side of the VPU 

device to prevent interference with the drink tube system 

2. Shorten the XM51 hood straps by approximately 2 inches (5.08 cm). 

3. Add an alignment indicator to ensure proper emplacement of filters during filter change-out 

or routine maintenance. 

4. Make the brow strap approximately 0.25 inch (0.64 cm) longer to accommodate Soldiers with 

a longer head length. 

5. Incorporate the air flow deflector of the current XM50 mask into the final design. 

6. Ensure that all warning and cautions in the operator card address the importance of proper 

emplacement of all disks and valves. 

7. Ensure that the mask is compatible with the current combat helmet systems. 

8. Conduct a future study that includes female participants to determine any wear issues and 

user acceptance of XM50 mask system. 

9. For future studies, the authors strongly encourage that a comparison questionnaire for each 

condition be administered after the completion of each trial. This is to compare perception of 

masks as the Soldier experiences each (Configuration A to B, A to C, etc.). 
34 

12. References 

Caretti, D. M.; Barker, D. J. Joint Service General Purpose Mask (JSGPM) Engineering Design 

Test (EDT) – Wearer Trials; U.S. Army Research Laboratory: Aberdeen Proving Ground, 

MD, 2002. 

Department of the Army. Ophthalmic Services, Army Regulation 40-63. Washington, DC, 

1986. 

Gordon, C. C.; Churchill, T.; Clauser, C. E.; Bradtmiller, B.; McConville, J. T.; Tebbetts, I.; 

Walker, R. A. 1988 Anthropometric Survey of U.S. Army Personnel: Summary Statistics 

Report 1989; Technical Report Natick/TR-89-027; U.S. Army Natick Research, 

Development, and Engineering Center: Natick, MA, 1989. 
35 

13. Bibliography 

Cohen, K. S. Protocol: ERDEC Field Element Protocol for Respiratory Protective System 21 

Demonstration; U.S. Army Research Laboratory: Aberdeen Proving Ground, MD, 1994. 

Departments of the Army and Air Force. Heat Stress Control and Heat Casualty Management; 

Technical Bulletin 507/Air Force Pamphlet 48-152 (I). Washington, DC, 2003. 

Joint Service Integration Group. Joint Service General Purpose Mask (JSGPM) Operational 

Requirements Document (ORD). Fort McClellan, AL, 30 September 1998. 

Science Applications International Corporation. Initial Safety Assessment Report for the Joint 

Service General Purpose Mask. Abington, MD, June 2001. 

U.S. Army Center for Health Promotion and Preventive Medicine. Health Hazard Assessment 

for the Joint Service General Purpose Mask. Aberdeen Proving Ground, MD, February 

1999. 

U.S. Army Soldier Biological and Chemical Command. Performance Specification, Joint 

Service General Purpose Mask. Aberdeen Proving Ground, MD, 1999. 
36 

INTENTIONALLY LEFT BLANK
Date of preparation of current version: 20050715 

Date of Human Use Committee Review: TBD 

Expiration Date: TBD Volunteer Initials______ Administrator Initials_________ 

37 

Appendix A. Volunteer Agreement Affidavit 

VOLUNTEER AGREEMENT AFFIDAVIT: 

ARL-HRED Local Adaptation of DA Form 5303-R. For use of this form, see AR 70-25 or AR 40-38 

The proponent for this research is: U.S. Army Research Laboratory 

Human Research and Engineering 

Directorate 

Aberdeen Proving Ground, MD 21005 

Authority: 

Privacy Act of 1974, 10 U.S.C. 3013, [Subject to the authority, direction, and 

control of the Secretary of Defense and subject to the provisions of chapter 6 of this 

title, the Secretary of the Army is responsible for, and has the authority necessary to 

conduct, all affairs of the Department of the Army, including the following 

functions: (4) Equipping (including research and development), 44 USC 3101 [The 

head of each Federal agency shall make and preserve records containing adequate 

and proper documentation of the organization, functions, policies, decisions, 

procedures, and essential transactions of the agency and designed to furnish the 

information necessary to protect the legal and financial rights of the Government 

and of persons directly affected by the agency's activities] 

Principal purpose: To document voluntary participation in the Research program. 

Routine Uses: 

The SSN and home address will be used for identification and locating purposes. 

Information derived from the project will be used for documentation, adjudication 

of claims, and mandatory reporting of medical conditions as required by law. 

Information may be furnished to Federal, State, and local agencies. 

Disclosure: 

The furnishing of your SSN and home address is mandatory and necessary to 

provide identification and to contact you if future information indicates that your 

health may be adversely affected. Failure to provide the information may preclude 

your voluntary participation in this data collection. 

Part A • Volunteer agreement affidavit for subjects in approved Department of Army research projects. 

Note: Volunteers are authorized medical care for any injury or disease that is the direct result of 

participating in this project (under the provisions of AR 40-38 and AR 70-25).

Title of Research Project: Joint Service General Purpose Mask (JSGPM) Human Systems Integration (HSI) 

Evaluation: Comfort and Vision Correction Insert Stability Evaluation 

Human Use Protocol Log # 

Number: 

ARL-20098-05044 

Principal Investigator: Lamar Garrett 

Phone: (410) 278-3413 

E-Mail: lgarrett@arl.army.mil

Associate Investigator(s) 

Sam Ortega 

Bill Harper 

Timothy White 

Phone: (410) 278-5990 

E-Mail: sortega@arl.army.mil

Phone: (410) 278-5955 

E-Mail: bharper@arl.army.mil

Phone: (410) 278-5884 

E-Mail: twhite@arl.army.mil

Location of Research: Fort Drum, New York 

Dates of Participation: 26 September 2005 – 3 October 2005 
Date of preparation of current version: 20050715 

Date of Human Use Committee Review: TBD 

Expiration Date: TBD Volunteer Initials______ Administrator Initials_________ 

38 

Part B • To be completed by the Principal Investigator 

Note: Instruction for elements of the informed consent provided as detailed explanation in 

accordance with 

Appendix C, AR 40-38 or AR 70-25. 

Purpose of the Research 

You are invited to participate in a study designed to evaluate the next generation Department of 

Defense (DoD) Nuclear, Biological and Chemical (NBC) protective mask, the Joint Service 

General Purpose Mask (JSGPM). The primary purpose of this evaluation is to: 1) assess the 

Soldier ability to don and doff the JSGPM, 2) assess the comfort level of the JSGPM with and 

without a modified mask beard in comparison to the M40 series mask, and 3) evaluate the vision 

correction insert and assess the spectacle insert stability and compatibility with the JSPGM 

prototype. The results will be used to create assessments and recommendations in support of the 

JSGPM, program. This evaluation is being conducted by the Army Research Laboratory (ARL), 

Human Research Engineering Directorate (HRED) at the request of the Product Manager for 

NBC Defense Systems from the Edgewood Chemical and Biological Command. 

Procedures 

After you have read and signed this Volunteer Agreement Affidavit, you will then be 

assigned a research participant number. Photographs and videotape may be used at any time 

during this study to adequately document evaluation conduct, problem areas or observations. 

You can refuse to have your picture taken if you wish. You will be given an opportunity to 

communicate any concerns to the investigators “off the record” and will be provided several 

options for refusing or withdrawing in a private manner. Your personal information and data 

recorded from experimental participants will be kept in a secured location in the offices of the 

Army Research Laboratory, Aberdeen Proving Ground, Maryland, building 459. 

Next, you will be asked to complete a health and demographics questionnaire. If you 

answer “yes” to any of the options given in question 1, 2, or 3 regarding ailments in the past 15 

days, you will be evaluated by a Physician Assistant prior to being permitted to participate in the 

evaluation. 

You will be screened for normal or corrected-to-normal visual acuity via examination 

with a Snellen eye chart and Titmus Vision Tester. Next, you will be fitted with a JSGPM 

w/hood and JSLIST (jacket only) and vision correction inserts, as required. 

Once you are issued and fitted with a JSGPM and individual protective equipment 

attached to your clothing, you will be trained how to use and maintain the XM50 using the 

methods provided during Instructor and Key Personnel Training (IKPT). Also, you will be 

trained how to complete all evaluation questionnaires. Prior to each evaluation trial, a visual 

inspection will be performed to ensure that all experimental and warfighter equipment are 

donned properly. 

You will complete a total of six trials, one trial per equipment configuration over the 
Date of preparation of current version: 20050715 

Date of Human Use Committee Review: TBD 

Expiration Date: TBD Volunteer Initials______ Administrator Initials_________ 

39 

course of 6 days. Each trial will require you to wear the JSGPM for a period of 3 hours. You 

will be given a 5-minute water break every 30 minutes during the trial. At the end of each trial 

you will remove your equipment and complete a 3 hour Wear Trial Questionnaire and a 3 hour 

Wear Comparative Questionnaire. Additionally, you will complete a Vision Correction Inserts 

Questionnaire if you wore vision correction inserts. You will be issued and fitted with a JSGPM 

w/hood, JSLIST (jacket only), and PASGT helmet. You will receive training on how to properly 

use, store and maintain the XM50. Following the training, you will be provided with a copy of 

the equipment configuration matrix. Total participation time will be 4 hours per day covering a 

period of 6 days, to include Saturday and Sunday. 

Benefits 

You will receive no direct benefits from participating in this study. However, the data 

you provide from this research will be the used to create performance assessments and design 

recommendations in support of the JSGPM. 

Participant’s Rights: Any published data will not reveal your identity. Your participation in 

this evaluation is voluntary. If you choose not to participate in this evaluation, or if later you 

wish to withdraw from any portion of it, you may do so without penalty. Military personnel are 

not subject to punishment under the Uniform Code of Military Justice for choosing not to take 

part as human subjects. No administrative sanctions can be taken against military or civilian 

personnel for choosing not to participate as human subjects. The furnishing of your social 

security number and home address is mandatory and necessary for identification and locating 

purposes to contact you if future information indicates that your health may be adversely 

affected. Failure to provide the information may preclude your voluntary participation in this 

study. Information derived from this study will be used to document the evaluation, to 

implement medical programs, to adjudicate claims, and for the mandatory reporting of medical 

conditions as required by law. Information may be furnished to Federal, State, and local 

agencies. Collection of this information is authorized by 10 USC 3013, 44 USC 3101, and 10 

USC 1071-1087. 

Under the provisions of AR 40-38 and AR 70-25, volunteers are authorized all necessary medical 

care for injury or disease which is the proximate result of their participation in this study. 

Risks 

Risks associated with this evaluation are minimal and are less than those encountered by 

war fighters during their normal operational field assignments. Heat stress and dehydration are 

considered the leading risks. You are advised that there are wild animals, snakes, and poisonous 

insects in the vicinity of some of the test sites and to take the appropriate precautions. All other 

risks anticipated in this evaluation are typical of the every day risks encountered by personnel 

working out of doors in this area. Flying insects at the test site are a concern. You will be 

encouraged to use insect repellent, which will be available on site. You will notify the principal 

investigator if you are bitten, and investigators will closely monitor you. You will be 

encouraged to use insect repellent, which will be available at the test site, and we ask that you 

inspect yourself frequently for insects. 
Date of preparation of current version: 20050715 

Date of Human Use Committee Review: TBD 

Expiration Date: TBD Volunteer Initials______ Administrator Initials_________ 

40 

The JSGPM design does not have any identified uncontrolled risks. The precautions pertinent to 

this evaluation apply to wear of all masks: There is the potential for skin rash or ammonia offgassing. The former problem occurs rarely. If it does occur, you simply stop participating and the 

rash goes away. For the latter problem, if you encounter a filter that has an ammonia off-gassing 

problem, inform one of the experimenters and the experimenters will replace the filter. There are 

no long-term medical hazards from the smell. Off-gassing filters will be labeled to record the 

problem. All masks will be cleaned with sanitary respirator wipes before use. Also, mask 

drinking system components will be sanitized before and after use. 

Members of the test administration staff will be close to you throughout all evaluation trials to 

assist you should a problem arise. If you ask to terminate the test, begin to have problems with 

your mask or if a mask becomes damaged, your participation in the evaluation will be stopped 

and your mask will be removed. Care will be taken to minimize risks. A copy of TB Med 507 

will be kept available at all times. If the WBGT equals or exceeds 75°F testing will be halted. 

Water will be available to you at all times. You will have a 5-minute water break every 30 

minutes during the trials. In addition, outdoor activities will be suspended during any weather 

conditions that are inherently dangerous or will cause evaluation trials to be dangerous. If it is 

raining or if there is an accumulation of water on the ground, outdoor test activities will be 

moved indoors, if conditions are believed to be unsafe. 

Confidentiality 

All data and information obtained about you will be considered privileged and held in 

confidence. Photographic or video images of you taken during this data collection will not be 

identified with any of your personal information (name, rank, or status). Complete 

confidentiality cannot be promised, particularly if you are a military service member, because 

information bearing on your health may be required to be reported to appropriate medical or 

command authorities. In addition, applicable regulations note the possibility that the U.S. Army 

Medical Research and Materiel Command (MRMC-RCQ) officials may inspect the records. 

Disposition of Volunteer Agreement Affidavit 

The Principal Investigator will retain the original signed Volunteer Agreement Affidavit and 

forward a photocopy of it to the Chair of the Human Use Committee after the data collection. 

The Principal Investigator will provide a copy of the signed and initialed Affidavit to you. 

Contacts for Additional Assistance 

If you have questions concerning your rights on research-related injury, or if you have any 

complaints about your treatment while participating in this research, you can contact: 

Chair, Human Use Committee OR Office of the Chief Counsel 

U.S. Army Research Laboratory U.S. Army Research Laboratory 

Human Research and Engineering Directorate 2800 Powder Mill Road 

Aberdeen Proving Ground, MD 21005 Adelphi, MD 20783-1197 

(520) 538-4705 or (DSN) 875-4705 (301) 394-1070 or (DSN) 290-1070 
Date of preparation of current version: 20050715 

Date of Human Use Committee Review: TBD 

Expiration Date: TBD Volunteer Initials______ Administrator Initials_________ 

41 

I do hereby volunteer to participate in the research project described in this document. I have full 

capacity to consent and have attained my 18th birthday. The implications of my voluntary 

participation, duration, and purpose of the research project, the methods and means by which it is 

to be conducted, and the inconveniences and hazards that may reasonably be expected have been 

explained to me. I have been given an opportunity to ask questions concerning this research 

project. Any such questions were answered to my full and complete satisfaction. Should any 

further questions arise concerning my rights or project related injury, I may contact the ARLHRED Human Use Committee Chairperson at Aberdeen Proving Ground, Maryland, USA 

by telephone at 410-278-4152 or DSN 298-4152. I understand that any published data will not 

reveal my identity. If I choose not to participate, or later wish to withdraw from any portion of it, 

I may do so without penalty. I understand that military personnel are not subject to punishment 

under the Uniform Code of Military Justice for choosing not to take part as human volunteers 

and that no administrative sanctions can be given me for choosing not to participate. I may at any 

time during the course of the project revoke my consent and withdraw without penalty or loss of 

benefits. However, I may be required (military volunteer) or requested (civilian volunteer) to 

undergo certain examinations if, in the opinion of an attending physician, such examinations are 

necessary for my health and well being. 

Printed Name of Volunteer (First, MI., Last)

Social Security Number (SSN) 

Date of Birth 

(Month, Day, Year)

Permanent Address of Volunteer 

Today’s Date 

(Month, Day, Year)

Signature of Volunteer 

Signature of Administrator 
42 

INTENTIONALLY LEFT BLANK
43 

Appendix B. Health and Demographics Questionnaire 

Health and Demographics Questionnaire

Participant Number: _____ Date: __________ 

1. Have you ever taken medication or been treated by a physician for any of the following 

ailments? (Please circle your response) 

 Dizziness or fainting spells Yes No 

 Chronic respiratory illness Yes No 

 Asthma Yes No 

 Shortness of breath Yes No 

 Heart trouble Yes No 

 High or low blood pressure Yes No 

 Chest pain with exercise Yes No 

 Diseases of the arteries Yes No 

 Diabetes Yes No 

 

2. Have you, in the past 15 days, taken medication or been treated by a physician for any of the 

following ailments? (Please circle you response) 

 Dizziness or fainting spells Yes No 

 Chronic respiratory illness Yes No 

 Asthma Yes No 

 Shortness of breath Yes No 

 Heart trouble Yes No 

 High or low blood pressure Yes No 

 Chest pain with exercise Yes No 

 Diseases of the arteries Yes No 

 Diabetes Yes No 

 

3. Do you have any other current or past ailments, which may prevent you from participating in 

the evaluation tasks described to you in the volunteer consent form? (Circle One): Yes No 

3a. If yes, please describe the ailment(s) below: 

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

__________________________________________ 
44 

4. Please circle the phrase that you feel best describes your history of tobacco use? 

(Circle One): Never Used Tobacco 

 Stopped more than 10 years ago 

 Stopped less than 10 years ago 

 Light User (less than one pack a per week) 

 Average User (more than one pack a per week) 

 Heavy User (more than one carton a week) 

4a. If you do use tobacco what type of tobacco do you use? (Circle all that apply): 

 Smoke Cigarettes 

Smoke Cigars 

Smoke a Pipe 

Chew Tobacco 

Use Snuff 

Other: __________ 

5. Please characterize your current regular aerobic exercise habits (e.g. jogging, cycling). 

(Circle One): Do not participate in regular aerobic exercise 

 Do aerobic exercise 1 to 3 times a week 

 Do aerobic exercise 4 to 5 times a week 

 Do aerobic exercise 6 to 7 times a week 

6. What is your branch of service? (Circle One): 

Air Force Army Marine Corps Navy Coast Guard 

7. What is your age? ______ 

 

8. How long have you been in the service? _____ years ______ months 

9. Please list below your primary MOS, ASI, NEC or AFS and briefly describe your job: 

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

_________________________________ 

9a. How long have you been performing this MOS, ASI, NEC or AFS? _____ years ______ 

months 

10. What is your gender? (Circle One): Male Female 

11. Do you wear vision correction devices (glasses, contact lenses)? (Circle One): 

Yes No 

11a. If yes, what type of vision correction device do you wear most often? 
45 

(Circle One): 

Glasses 

Contact Lenses 

Other: ____________ 

12. Do you typically wear vision corrective inserts with your current protective mask? 

(Circle One): 

Yes No 

13. Please rate your perceived level of experience with protective mask systems. 

(Circle One): 

Very Experienced Experienced Slightly Experienced Not Experienced 

14. If applicable, please circle all masks with which you have experience. 

(Circle all that apply): 

M40 series M42 M17 M45 Other:__________ 

15. If applicable, please circle the mask you currently use. 

(Circle One): 

 M40 series M42 M17 M45 Other:__________ 

16. Have you ever had an adverse reaction, before, during or after wearing a mask? 

(Circle One): 

Yes No 

16a. If yes, please describe this reaction in detail: 

________________________________________________________________________ 

______________________________________________________________________________

__________________________________________________________________ 

17. What is your education level? 

(Circle One): 

GED 

12 years (High School Graduate) 

 13-15 years (Some College) 

 16 years (College Graduate) 

 Greater than 16 years (Post Graduate Education) 
46 

INTENTIONALLY LEFT BLANK
47 

Appendix C. Anthropometrics Measurement Summary 

Table C-1. Summary of range, minimum, maximum, mean, standard error, and standard deviation for anthropometric measures and percentiles. 

 N Range Min Max Mean Std. 

Error 

Std. 

Dev. 

STATURE 21 20.1 166.8 186.9 176.26 1.06 4.87 

STATURE % 21 85 10 95 53.10 5.02 22.99 

WEIGHT 21 38.2 58.5 96.7 81.68 2.57 11.76 

WEIGHT % 21 92 2 94 58.52 6.89 31.59 

BITRAGION CORONAL ARC 21 4.0 32.6 36.60 34.98 0.24 1.09 

BITRAGION CORONAL ARC % 21 82 2 84 43.10 5.70 26.12 

BITRAGION CRINION ARC 21 7.5 28.6 36.10 32.42 0.37 1.67 

BITRAGION CRINION ARC % 21 98 1 99 46.14 6.76 30.98 

BITRAGION FRONTAL ARC 21 7.2 27.2 34.40 30.45 0.32 1.45 

BITRAGION FRONTAL ARC % 21 98 1 99 50.48 6.32 28.98 

BITRAGION SUBNASALE ARC 21 6.4 25.5 31.90 29.15 0.32 1.43 

BITRAGION SUBNASALE ARC % 21 98 1 99 48.52 7.17 32.87 

BITRAGION CHIN ARC 21 7.2 28.0 35.20 32.16 0.39 1.77 

BITRAGION CHIN ARC % 21 96 1 97 41.38 7.19 32.97 

BITRAGION SUBMANDIBULAR ARC 21 5.9 27.2 33.10 30.27 0.33 1.52 

BITRAGION SUBMANDIBULAR ARC % 21 95 1 96 44.33 6.90 31.60 

HEAD CIRCUMFERENCE 21 9.8 52.8 62.60 56.80 0.42 1.94 

HEAD CIRCUMFERENCE % 21 98 1 99 50.19 6.09 27.90 

BIZYGOMATIC BREADTH 21 2.5 12.7 15.20 14.10 0.13 .618 

BIZYGOMATIC BREADTH % 21 96 1 97 54.95 6.93 31.76 

HEAD BREADTH 21 2.6 13.80 16.40 15.33 0.15 .67 

HEAD BREADTH % 21 97 1 98 60.52 6.88 31.52 

HEAD LENGTH 21 4.1 18.4 22.5 19.78 0.18 .87 

HEAD LENGTH % 21 96 3 99 49.96 6.31 30.90 

INTERPUPILLARY BREADTH 21 1.7 5.7 7.4 6.40 0.09 .43 

INTERPUPILLARY BREADTH % 21 98 1 99 45.88 6.47 31.70 
48 

Table C-2. Summary of anthropometric data 

TP 

No. 

Bitragion 

Crinion Arc 

(cm) 

Bitragion 

Crinion Arc 

% 

Bitragion 

Frontal Arc 

(cm) 

Bitragion 

Frontal Arc 

% 

Bitragion 

Subnasale 

Arc (cm) 

Bitragion 

Subnasale 

Arc % 

3 31.50 17 30.00 35 30.40 86 

7 32.60 50 30.20 42 28.80 36 

9 36.10 99 34.40 99 31.90 99 

12 32.50 46 29.70 25 28.50 27 

13 32.80 57 31.50 84 30.50 88 

14 32.40 43 31.10 74 29.80 71 

15 28.60 1 28.10 1 28.00 14 

16 29.30 1 27.20 1 25.50 1 

18 31.70 21 30.00 35 28.60 30 

20 33.60 80 31.90 91 30.90 93 

21 32.50 46 30.20 42 27.90 12 

22 33.80 84 31.80 90 30.70 91 

24 32.20 36 30.60 57 28.50 27 

25 35.10 98 30.60 57 28.30 21 

26 31.20 11 29.90 32 28.70 33 

27 31.60 19 30.40 50 28.30 21 

28 32.10 33 30.50 53 29.20 50 

30 33.70 82 31.30 79 30.90 93 

34 31.30 13 28.90 7 28.10 16 

35 33.20 69 30.20 42 29.90 74 

36 33.00 63 30.80 64 28.80 36 

TP 

No. 

Stature (cm) Stature % Weight (kg) Weight % Bitragion 

Coronal Arc 

(cm) 

Bitragion 

Coronal Arc 

% 

3 170.8 24 75.4 42 34.80 34 

7 177.1 59 80.3 59 34.90 37 

9 177.6 62 94.6 91 36.60 84 

12 176.4 55 68.4 18 35.30 49 

13 176.3 55 95.8 93 36.10 73 

14 185.6 93 66.9 14 33.90 13 

15 186.9 95 83.8 70 32.60 2 

16 169.4 18 58.5 2 33.30 6 

18 178.6 68 79.8 58 34.50 26 

20 166.8 10 96.7 94 35.80 65 

21 175.2 48 70.6 25 35.70 62 

22 175.8 52 91.2 87 36.10 73 

24 175.5 50 72.8 32 34.60 28 

25 181.0 79 95.8 93 35.70 62 

26 174.0 41 85.7 76 34.10 17 

27 172.8 34 66.2 13 33.20 5 

28 180.6 77 78.3 52 35.90 67 

30 176.6 56 96.3 93 34.90 37 

34 171.3 27 76.0 44 35.70 62 

35 179.2 71 93.2 90 36.20 75 

36 174.0 41 89.0 83 34.60 28 
49 

TP 

No. 

Bitragion Chin Arc 

(cm) 

Bitragion Chin Arc 

% 

Bitragion 

Submandibular Arc 

(cm) 

Bitragion 

Submandibular Arc 

% 

3 32.70 54 31.50 77 

7 32.40 45 30.80 62 

9 35.10 97 31.20 71 

12 30.70 8 28.80 13 

13 35.20 97 33.10 96 

14 32.50 48 29.50 27 

15 31.20 15 29.20 20 

16 28.00 1 27.20 1 

18 31.20 15 30.50 53 

20 34.20 88 31.00 66 

21 30.20 4 28.30 7 

22 34.80 95 32.00 86 

24 32.30 42 29.00 16 

25 31.10 13 30.90 10 

26 31.90 31 29.80 34 

27 31.90 31 29.00 16 

28 32.10 36 30.30 48 

30 33.70 80 32.80 94 

34 30.50 6 29.70 32 

35 32.60 51 31.90 84 

36 31.00 12 29.10 18 

TP 

No. 

Head 

Circumference (cm) 

Head 

Circumference % 

Bizygomatic 

Breadth 

(cm) 

Bizygomatic 

Breadth % 

Head 

Breadth 

(cm) 

Head 

Breadth % 

3 55.80 27 14.80 90 16.10 95 

7 57.00 57 13.90 41 15.20 54 

9 62.60 99 14.60 84 15.60 80 

12 57.10 59 14.10 56 15.20 54 

13 58.20 83 14.70 87 15.40 68 

14 58.30 84 14.00 49 15.50 74 

15 53.80 2 13.20 6 14.30 5 

16 52.80 1 12.70 1 13.80 1 

18 56.80 51 13.30 8 14.30 5 

20 57.10 59 14.50 80 15.20 54 

21 55.60 23 14.20 62 15.40 68 

22 56.60 46 15.20 97 15.70 84 

24 57.10 59 13.70 27 15.20 54 

25 55.90 29 14.30 69 16.30 98 

26 57.00 57 13.50 16 15.40 68 

27 56.10 33 13.40 12 14.50 10 

28 57.20 62 14.50 80 16.40 98 

30 58.50 87 14.50 80 15.90 91 

34 54.70 9 14.00 49 15.30 61 

35 57.80 76 14.50 80 16.10 95 

36 56.80 51 14.50 80 15.20 54 
50 

TP 

No. 

Head Length 

(cm) 

Head Length % Interpupillary 

Breadth (cm) 

Interpupillary 

Breadth % 

3 18.90 12 6.40 44 

7 20.00 66 6.10 16 

9 22.50 99 7.40 99 

12 20.20 76 6.40 44 

13 20.30 80 6.75 78 

14 20.30 80 6.70 74 

15 18.40 3 6.30 34 

16 18.60 6 5.70 1 

18 20.00 66 6.25 29 

20 19.60 43 7.05 93 

21 19.00 15 6.05 13 

22 19.70 49 6.40 44 

24 20.70 92 6.45 50 

25 19.00 15 6.25 29 

26 20.00 66 6.60 65 

27 19.60 43 6.70 74 

28 19.20 23 6.70 74 

30 20.70 92 6.60 65 

34 19.20 23 5.70 1 

35 20.00 66 5.85 4 

36 19.60 43 6.70 74 
51 

Appendix D. Vision Correction Inserts Questionnaire 

Vision Correction Inserts Questionnaire

Participant Number: _____ Configuration: A B C D Date: __________ 

 

For the following questions place a check in the box next to the response that best describes 

your opinion of the equipment you wore during this trial. 

1. The vision corrective inserts inside of 

the mask were: 

2. Vision through the JSGPM vision 

corrective inserts was: 

 

 Very Stationary  Very Clear 

 Stationary  Clear 

 Slightly Stationary  Slightly Clear 

 Slightly Unstationary  Slightly Hazy 

 Unstationary  Hazy 

 Very Unstationary  Very Hazy 

 

3. When moving your head up and down 

the vision corrective inserts were: 

4. When moving your head left and right 

the vision corrective inserts were: 

 

 Very Stable  Very Stable 

 Stable  Stable 

 Slightly Stable  Slightly Stable 

 Slightly Unstable  Slightly Unstable 

 Unstable  Unstable 

 Very Unstable  Very Unstable 

 

5. Depth Perception while wearing the 

mask with vision corrective inserts was: 

6. Glare created by the mask lenses while 

wearing vision corrective inserts was: 

 Very Good  Very Common 

 Good  Common 

 Slightly Good  Slightly Common 

 Slightly Poor  Slightly Uncommon 

 Poor  Uncommon 

 Very Poor  Very Uncommon 
52 

7. Left and Right field of view while 

wearing vision corrective inserts was: 

8. Up and Down field of view while 

wearing vision corrective inserts was: 

 

 Very Good  Very Good 

 Good  Good 

 Slightly Good  Slightly Good 

 Slightly Poor  Slightly Poor 

 Poor  Poor 

 Very Poor  Very Poor 

9. Overall, the vision corrective inserts 

were: 

10. The impact of the mask while 

wearing vision corrective inserts while 

performing your duties was: 

 

 Very Comfortable  Extreme Impact 

 Comfortable  Moderate Impact 

 Slightly Comfortable  Slight Impact 

 Slightly Uncomfortable  No Impact (as if you were not 

wearing a mask) 

 Uncomfortable 

 Very Uncomfortable 

 

11. Was your vision obstructed while wearing vision corrective inserts?  Yes  No 

12. If yes, please describe the obstruction in detail: 

______________________________________________________________________________

______________________________________________________________________________

____________________________________________________________ 

13. Did the mask fog up or accumulate any sweat while wearing vision corrective inserts during 

this trial?  Yes  No 

14. If yes, did fog up or accumulate sweat, which eye? 

 Left  Right  Both 

15. How much did the fogging or sweat accumulation affect your performance? 

Extremely  Moderately  Slightly  Not at all 

16. Did the vision correction inserts pinch or cut your skin?  Yes  No 

17. If the vision correction inserts did pinch or cut your skin, please describe in detail: 

______________________________________________________________________________

______________________________________________________________________________

____________________________________________________________ 
53 

18. Did movement, did the world seem to jump or move while wearing the vision correction 

inserts.  Yes  No 

19. If the world seems to jump or move, please describe in detail: 

______________________________________________________________________________

______________________________________________________________________________

____________________________________________________________ 

20. Did you experience any pressure points while wearing vision corrective inserts during this 

trial?  Yes  No 

21. If you did experience pressure points, please describe feeling and the location in detail: 

______________________________________________________________________________

______________________________________________________________________________

____________________________________________________________ 

22. Did the vision correction inserts dislodge from the mask at any time during this trial?  Yes 

 No 

23. If the vision correction inserts did dislodged, please describe how in detail: 

______________________________________________________________________________

______________________________________________________________________________

____________________________________________________________ 

 24. Please list any additional comments you may have concerning the vision corrective inserts: 

______________________________________________________________________________

______________________________________________________________________________

____________________________________________________________ 
54 

INTENTIONALLY LEFT BLANK
55 

Appendix E. Comfort (3 hour Wear Time) Trial Questionnaire 

3 hour Wear Trial Questionnaire

Participant Number: _____ Configuration: A B C D Date: __________ 

Helmet (Circle One): No Helmet PASGT MICH 

 

For the following questions put a check in the box next to the response that best describes 

your opinion. 

1. The mask around the eyes was: 

2. The mask periphery (around the 

combined contact points of the head, 

temples cheek and chin) was: 

 

 Very Comfortable  Very Comfortable 

 Comfortable  Comfortable 

 Slightly Comfortable  Slightly Comfortable 

 Slightly Uncomfortable  Slightly Uncomfortable 

 Uncomfortable  Uncomfortable 

 Very Uncomfortable  Very Uncomfortable 

 

3. The mask’s nosecup was: 4. The mask’s head harness was: 

 

 Very Comfortable  Very Comfortable 

 Comfortable  Comfortable 

 Slightly Comfortable  Slightly Comfortable 

 Slightly Uncomfortable  Slightly Uncomfortable 

 Uncomfortable  Uncomfortable 

 Very Uncomfortable  Very Uncomfortable 

 

5. The mask around the throat was: 6. The mask around the neck area was: 

 

 Very Comfortable  Very Comfortable 

 Comfortable  Comfortable 

 Slightly Comfortable  Slightly Comfortable 

 Slightly Uncomfortable  Slightly Uncomfortable 

 Uncomfortable  Uncomfortable 

 Very Uncomfortable  Very Uncomfortable 
56 

7. The mask at your chin was: 8. The mask at your forehead was: 

 

 Very Comfortable  Very Comfortable 

 Comfortable  Comfortable 

 Slightly Comfortable  Slightly Comfortable 

 Slightly Uncomfortable  Slightly Uncomfortable 

 Uncomfortable  Uncomfortable 

 Very Uncomfortable  Very Uncomfortable 

9. The mask overall was: 10. The weight of the mask was: 

 

 Very Comfortable  Very Comfortable 

 Comfortable  Comfortable 

 Slightly Comfortable  Slightly Comfortable 

 Slightly Uncomfortable  Slightly Uncomfortable 

 Uncomfortable  Uncomfortable 

 Very Uncomfortable  Very Uncomfortable 

 

11. The thermal conditions of your face 

inside of the mask were: 

12. The weight of the mask and helmet 

combined was: 

 

 Very Comfortable  Very Comfortable 

 Comfortable  Comfortable 

 Slightly Comfortable  Slightly Comfortable 

 Slightly Uncomfortable  Slightly Uncomfortable 

 Uncomfortable  Uncomfortable 

 Very Uncomfortable  Very Uncomfortable 

 

13. Wearing the mask carrier was: 14. Inhaling through the mask while 

performing this trial was: 

 

 Very Comfortable  Very Easy 

 Comfortable  Easy 

 Slightly Comfortable  Slightly Easy 

 Slightly Uncomfortable  Slightly Difficult 

 Uncomfortable  Difficult 

 Very Uncomfortable  Very Difficult 
57 

15. Exhaling through the mask while 

performing this trial was: 

16. The fit of the mask was: 

 

 Very Easy  Very Good 

 Easy  Good 

 Slightly Easy  Slightly Good 

 Slightly Difficult  Slightly Poor 

 Difficult  Poor 

 Very Difficult  Very Poor 

17. Please discuss in detail any compatibility problems you may have experienced between the 

mask and the individual equipment you wore during this trial: 

______________________________________________________________________________

______________________________________________________________________________

____________________________________________________________ 

 

18. Please discuss in detail any comfort related comments or issues you may have experienced 

during this trial: 

______________________________________________________________________________

______________________________________________________________________________

____________________________________________________________ 
58 

INTENTIONALLY LEFT BLANK
59 

Appendix F. 3 hour Wear Trial Comparative Questionnaire 

3 hour Wear Trial Comparative Questionnaire

Participant Number: ___ Configuration (Circle One): A B C D Date: _______ 

Helmet (Circle One): No Helmet PASGT MICH 

 

For the following questions put a check in the box next to the response that best describes 

your opinion. 

1. Compared to your current mask system, 

the comfort of the XM50/51 after three 

hours of wear, was: 

2. Compared to your current mask system, 

the comfort of the XM50/51 when worn 

with MOPP Gear and helmet was: 

 

  Much Better  Much Better 

 Better  Better 

 Slightly Better  Slightly Better 

 Slightly Worse  Slightly Worse 

 Worse  Worse 

 Much Worse  Much Worse 

 

3. Compared to your current mask system, 

XM50/51 breathing resistance during 

inhalation was: 

4. Compared to your current mask system, 

XM50/51 breathing resistance during 

exhalation was: 

 

 Much Better  Much Better 

 Better  Better 

 Slightly Better  Slightly Better 

 Slightly Worse  Slightly Worse 

 Worse  Worse 

 Much Worse  Much Worse 

 

5. Compared to your current mask system, 

the fit of the XM50/51 was: 

6. Compared to your current mask system, 

XM50/51 your field of view was: 

 

 Much Better  Much Better 

 Better  Better 

 Slightly Better  Slightly Better 

 Slightly Worse  Slightly Worse 

 Worse  Worse 

 Much Worse  Much Worse 

 
60 

7. Compared to your current mask carrier, 

the XM50/51 modular two bag carrier 

system was: 

8. Compared to your current mask system, 

removing the XM50/51 air deflectors from 

the mask was: 

 

 Much Better  Very Easy 

 Better  Easy 

 Slightly Better  Slightly Easier 

 Slightly Worse  Slightly Difficult 

 Worse  Difficult 

 Much Worse  Very Difficult 

 

9. Compared to your current mask system, 

installing the XM50/51 air deflectors from 

the mask was: 

10. Compared to your current mask 

system, removing the XM50/51 inhalation 

valve from the filter mount was: 

 

 Very Easy  Very Easy 

 Easy  Easy 

 Slightly Easier  Slightly Easier 

 Slightly Difficult  Slightly Difficult 

 Difficult  Difficult 

 Very Difficult  Very Difficult 

 

11. Compared to your current mask 

system, installing the XM50/51 inhalation 

valve from the filter mount was: 

12. Compared to your current mask 

system, removing the XM50/51 self 

sealing valve from the filter mount was: 

 

 Very Easy  Very Easy 

 Easy  Easy 

 Slightly Easier  Slightly Easier 

 Slightly Difficult  Slightly Difficult 

 Difficult  Difficult 

 Very Difficult  Very Difficult 

 Not Applicable 

 

13. Installing the XM 50/51 self sealing 

valve from the filter mount was: 

14. Having filter alignment marks on the 

XM50/51 during filter change-out was: 

 

 Very Easy  Very Useful 

 Easy  Useful 

 Slightly Easier  Slightly Useful 

 Slightly Difficult  Slightly Useless 

 Difficult  Useless 

 Very Difficult  Very Useless 

 Not Applicable 

 
61 

15. Accidentally detaching the XM50/51 

filter during filter change-out was: 

16. Accidentally detaching the XM50/51 

self sealing valve from the filter mount 

during filter change-out was: 

 

 Very Common  Very Common 

 Common  Common 

 Slightly Common  Slightly Common 

 Slightly Uncommon  Slightly Uncommon 

 Uncommon  Uncommon 

 Very Uncommon  Very Uncommon 
62 

INTENTIONALLY LEFT BLANK
63 

Appendix G. Demographics and Vision Summary 

Table G-1. Demographic data summary 

Soldier 

ID No. 

Age 

(years) 

Time in 

Service 

(months) 

Grade MOS 

3 23 37 E-4 11B 

4 25 19 E-3 13D 

7 23 33 E-4 25F 

8 22 50 E-3 11B 

9 20 12 E-3 91W 

12 19 18 E-3 11B 

13 22 17 E-3 74D 

14 21 33 E-4 74D 

15 21 36 E-4 74D 

16 32 108 E-5 11B 

18 20 27 E-4 98C 

20 30 119 E-5 74D 

21 23 17 E-3 63J 

22 38 241 E-6 74D 

23 28 48 E-4 88M 

24 20 13 E-1 88M 

25 34 60 E-4 21B 

26 22 51 E-4 11B 

27 20 21 E-3 19D 

28 22 22 E-4 74D 

30 35 108 E-5 74D 

34 20 7 E-2 19D 

35 28 58 E-4 21B 

36 26 30 E-4 74D 
64 

Table G-2. Vision screening summary 

Soldier 

ID No.

Corrective 

Eye Wear 

Dominant 

Eye 

Far Visual Acuity 

Both 

Eyes 

Color 

Vision

3 Yes R 20/50 Normal 

4 No R 20/30 Normal 

7 No R 20/20 Normal 

8 Yes R 20/40 Normal 

9 Yes R 20/13 Normal 

12 No R 20/18 Normal 

13 No R 20/30 Normal 

14 No R 20/20 Normal 

15 No R 20/25 Normal 

16 No R 20/25 Normal 

18 No R 20/13 Normal 

20 No R 20/17 Normal 

21 Yes R 20/22 Normal 

22 No R 20/17 Abnormal 

23 No L 20/13 Normal 

24 No R 20/18 Normal 

25 Yes L 20/20 Normal 

26 Yes R 20/18 Normal 

27 No R 20/13 Normal 

28 Yes R 20/13 Normal 

30 No R 20/13 Normal 

34 Yes L 20/22 Normal 

35 No R 20/17 Normal 

36 Yes R 20/15 Normal 
65 

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