TN-25965 Lower Merion Fire Department PA 1

PPE CASE

Personal Protective Equipment Conformity Assessment Studies and Evaluations

Evaluation of a Self-Contained Breathing Apparatus Involved in a 

Fatality While Operating at a Structure Fire

Lower Merion Fire Department, PA, Requested the Evaluation of a MSA Model G1, 30-

minute, 4500 psi unit

National Institute for Occupational Safety and Health (NIOSH) 

National Personal Protective Technology Laboratory (NPPTL)

Angie Andrews, Jay Tarley

November 3, 2022

The National Institute for Occupational Safety and Health (NIOSH) 

conducts a Fire Fighter Fatality Investigation and Prevention Program, 

which is executed by its Division of Safety Research (DSR). In support of 

this Program, NIOSH’s National Personal Protective Technology 

Laboratory (NPPTL) inspects and evaluates the self-contained breathing 

apparatus (SCBA) used by the firefighter during a fatality. 

This report provides a summary of NPPTL’s inspection and 

evaluation methods, as well as findings for testing related to an 

SCBA that was being used by a firefighter from the Lower Merion 

Fire Department during a fatal event. The SCBA used was an MSA 

Model G1, 30-minute, 4500 psi unit.

What NIOSH Did to Protect the Worker

Upon receipt of the SCBA, NPPTL managed the custody of evidence throughout the entire inspection and 

evaluation process at its Morgantown, West Virginia, facility. NPPTL staff inspected all SCBA components and 

documented their findings with written and photographic evidence. NIOSH assigned Task Number TN-25965 to 

identify the unit. NPPTL also tested the SCBA to determine conformance to NPPTL’s approval requirements as 

outlined in Title 42, Code of Federal Regulations, Part 84 (42 CFR 84). Further testing was conducted to provide 

an indication of the conformance of the SCBA to the National Fire Protection Association (NFPA) Airflow 

Performance requirements of NFPA 1981, Standard on Open-Circuit Self-Contained Breathing Apparatus for the 

Fire Service, 2013 Edition. This unit was certified to the 2013 Edition, therefore was evaluated to the 2013 

NIOSH received an SCBA 

used by a firefighter 

involved in a fatality. The 

SCBA was not found to 

contribute to the fatality. 

A qualified service 

technician must inspect, 

repair, test, clean, and 

replace damaged 

components of any SCBA 

involved in an incident 

before it may be returned to 

service.
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Edition – there is no difference between the NFPA Airflow Performance requirements of NFPA 1981 2019 

Edition and the 2013 Edition. If the inspection or evaluation data suggested that the SCBA unit may have 

contributed to the fatal event, NPPTL would have engaged in corrective action to ensure that no other users of a 

SCBA with NIOSH Approval Number TC13F-0786CBRN would experience a fatal event. In this case, no such 

corrective action was necessary. NPPTL then managed the disposition of the SCBA.

Chain of Custody

The SCBA unit was delivered via FedEx in cardboard boxes to Lab H1513 for secure storage in the NIOSH facility 

in Morgantown, West Virginia, on June 23, 2022. The SCBA unit remained in secure storage in Lab H1513 

throughout the inspection and testing process. 

SCBA Inspection

On June 28, 2022, NPPTL employees Jay Tarley and Angie Andrews inspected the SCBA unit. The SCBA was

identified as belonging to the Lower Merion Fire Department and was visually examined, component by

component, in the condition received to determine the conformance of the unit to its NIOSH-approved

configuration. The unit was an MSA Model G1, 30-minute, 4500 psi with NIOSH Approval Number TC-13F0786CBRN. 

As-received 

• The SCBA unit was delivered by FedEx. 

• The cylinder was received empty and was closed. 

• The bypass was closed. 

• The mask-mounted regulator (MMR) was securely connected to the medium-pressure hose. 

Figure 1: SCBA as-received
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Figure 2: SCBA as-received out of packaging
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Components and Observations for the SCBA 

The “right” or “left” are from the user’s perspective; “good” means functional and may show signs of dirt/soot; “fair” 

means functional, but with signs of some damage; “bad” means not functional, needs to be inspected by technician to 

possibly replace part(s). (See Figures in Appendix 2)

Facepiece (Figures 3-6) 

• Facepiece seal P/N: 10161810; M/N: 7-2771-1 (1)

• Nosecup MFG date: 8/2018 

• Overall condition was good condition 

• Lens was scratched yet in good condition

• Upper lens ring was in good condition

• Lens retaining ring was intact

• MMR housing was clean and in good condition; M/N 7-

2774-1; 10144170 VMQ

• HUD was present and intact

• Head harness was in good condition with dirt present 

• Bottom facepiece lug broken; top right head harness strap 

not hooked to mask

Mask-Mounted Regulator (MMR) (Figures 7-9)

• MMR label on front: MSA; M/N: 7-2779-1 TEC

• Overall condition was good with signs of dirt

• MMR was secured to medium-pressure hose; electrical 

line not attached

• Bypass closed

• Inside flange had normal wear and was in good condition 

• Sealing area was good and slightly dirty

• Regulator could be attached and removed

• Outer rubber in good condition

• RFID stamp was present

Medium-Pressure Regulator Hose (Figures 9-10) 

• Secured at all attachment points

• Line was in good condition 

• Line passed through the shoulder strap to the reducer

Pressure Reducer Assembly (Figures 11-12) 

• Overall condition was good

• All airline connections were secure

• All lines going to the pressure reducer were in good 

condition

PASS Control Module (Figures 13-15) 

• Lines to control module looked good

• Gauge lens was not readable

• Protective boot was good and in place 

• M/N 7-3006-1 

High-Pressure Hose and Cylinder Attachment (Figures 16-17) 

• High-pressure line was in good condition; M/N: 7-2844-1, 

0619 

• Cylinder quick connect attachments 4500/5500 psi, P/N 

10149702-SP, some heat damage and dirty

Quick-Fill line (Figures 18-19) 

• Protective cover and sleeve in good condition 

PASS Power Module (Figures 20-23) 

• SEI label:02-2019; 10148686 4500 psi; RFID

• SEI label states this PASS met requirements of NFPA 1982: 

Standard on Personal Alert Safety Systems (PASS), 2013 

edition 

• Overall condition was good 

• Li-ion Rechargeable Battery Pack 7-2814-1 

• Held securely to backplate, signs of heat damage

• Power module battery; M/N 7-2814-1; P/N 10148741 

Backplate Assembly (Figure 24) 

• SEI label indicated unit met NFPA 1981 2013 edition 

• NIOSH Approval Number label: TC-13F-0786CBRN

• FD label with SCBA 09

• Overall condition was good 

• Shoulder straps were attached to the frame 

Straps and Buckles (Figures 25-26) 

• Overall condition of straps was good

• Hose lines passed through shoulder straps 

• All adjustable buckles moved and held in place 

• Lumbar strap not attached

• Waist area buckle latched 

Compressed Air Cylinder and Cylinder Valve Assembly (Figures 

27-31)

• DOT-SP 10915-4500; TC-3CCM-310 

• Luxfer L45R-52; ACT193169; REE: 86 

• MSA M/N 7-947-1 

• Manufacturer date: 12/2018; 30-minute, 4500 PSI

• Received with no air

• Overall condition was good with signs of heat damage to 

label

• Gauge had heat damage; not sure if functional

• Threads were good 

• O-ring was present and in good condition 

• Rubber boot at base of cylinder valve was in good 

condition 

• FD labels 21 09
 

 

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SCBA Testing

The SCBA unit was tested using six NIOSH standard testing procedures and one NFPA test method as described in Table 1 and Table 2.

Table 1. Summary of results from NIOSH standard testing procedures.

NIOSH Tests Description of Results PASS/

FAIL 

Positive Pressure Test - NIOSH Standard Testing Procedure Number 120, 42 CFR Part 84 Reference: 

Subpart H, § 84.70 (a)(2)(ii)

Requirement: 

The pressure inside the facepiece in relation to the immediate environment is positive

during both inhalation and exhalation.

Procedure: 

A breathing machine with a 622 kg-m/min cam operating at 24 RPM with a 40 liters per minute flow 

rate (115 liters per minute peak flow) is connected to an anthropometric head for cycling. A pressure 

tap in the head is connected to a transducer which in turn is connected to LabVIEW for determining 

the pressure in the facepiece.

The unit met the test requirement. The 

inhalation breathing resistance did not become 

negative during the test. 

Inhalation Breathing Resistance: (inches of 

water column) = 0.05 PASS

Rated Service Time Test - NIOSH Standard Testing Procedure Number 121, 42 CFR Part 84 

Reference: Subpart F, § 84.53 (a) and Subpart H, § 84.95 (a) and (b)

Requirement: 

Service time will be measured while the apparatus is operated by a breathing machine as described in 

§ 84.88. The open-circuit apparatus will be classified according to the length of time it supplies air or 

oxygen to the breathing machine. Classifications are listed in § 84.53.

Procedure: 

A breathing machine with a 622 kg-m/min cam operating at 24 RPM with a 40 liters per minute flow 

rate is connected to an anthropometric head for cycling. A pressure tap in the head is connected to a 

transducer which in turn is connected to LabVIEW for determining the pressure in the facepiece. The 

breathing machine is run until the inhalation portion of the breathing curve falls below the minimum 

requirement.

The unit met the test requirements. The 

measured service time (adjusted to correspond 

with the recorded breathing cycles) was more 

than the rated service time of 30 minutes. The 

SCBA did not go negative on inhalation;

therefore, positive pressure was maintained in 

the facepiece

Measured Service Time: 

34 Minutes 53 Seconds PASS 
 

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Exhalation Resistance Test - NIOSH Standard Testing Procedure Number 122, 42 CFR Part 84 

Reference: Subpart H, § 84.91 (c)

Requirement: 

The exhalation resistance of pressure-demand apparatus shall not exceed the static pressure in the 

facepiece by more than 51 mm (2 inches) water column height.

Procedure: 

The facepiece is mounted on an anthropometric headform. A probe in the headform is connected to 

a slant manometer for measuring exhalation breathing resistance. The airflow through the apparatus 

is adjusted to a rate of 85 liters per minute and the exhalation resistance is recorded.

The SCBA met the test requirement. 

Exhalation Breathing Resistance: (inches of 

water column) = 1.93

Static Pressure: (inches of water

column) = 0.75

Difference: (inches of water column) = 1.18 PASS

Static Pressure Test - NIOSH Standard Testing Procedure Number 122, 42 CFR Part 84 Reference: 

Subpart H, § 84.91 (d)

Requirement:

The static pressure (at zero flow) in the facepiece shall not exceed 38 mm (1.5 inches) water column

height.

Procedure: 

The facepiece is fitted to an anthropometric head for testing. A pressure tap in the head is connected 

to a calibrated manometer. Full cylinder pressure is applied to the unit at zero flow and a reading 

from the manometer is recorded.

The SCBA met the test requirement. 

Facepiece Static Pressure: (inches of water

column) = 0.75 PASS

Gas Flow Test - NIOSH Standard Testing Procedure Number 123, 42 CFR Part 84 Reference: 

Subpart H, § 84.93 (b) and (c)

Requirement: 

The flow from the apparatus shall be greater than 200 liters per minute when the pressure in the 

facepiece of demand apparatus is lowered by 51 mm (2 inches) water column height when full 

container pressure is applied. Where pressure demand apparatus are tested, the flow will be 

measured at zero gauge pressure in the facepiece.

Procedure: 

A pressure tap in the anthropometric head is connected to a manometer for determining when the 

pressure inside the facepiece is at zero. A mass flow meter is connected in line between the 

anthropometric head and an adjustable vacuum source to measure flow. The SCBA cylinder is 

replaced by a test stand which is adjusted initially to full cylinder pressure. The vacuum source is 

adjusted during the test to maintain the desired pressure inside the facepiece. Once the proper 

facepiece pressure has stabilized, a flow reading is recorded. The procedure is then repeated with 

the test stand adjusted to 500 psig.

The SCBA met the test requirement. 

Applied Pressure Airflow (liters per minute)

4500 psig 410.6

500 psig 280.3

PASS 

PASS
 

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Remaining Service Life Indicator Test - NIOSH Standard Testing Procedure Number 124, 42 CFR Part 

84 Reference: Subpart H, § 84.83 (f) and Subpart G, § 84.63 (c)

Requirement: 

Each remaining service-life indicator or warning device must give an alarm when the remaining 

service life is reduced to a minimum of 25 percent of its rated service time, or any higher minimum 

percent value or values as specified in the approval. Open-circuit demand and pressure-demand 

respirators must alarm continuously until depletion of the breathing air supply. The percent value set 

for indicator activation must be identified by labels and/or markings on each respirator unit.

Procedure: 

A calibrated gauge is connected in line between the air supply and the first stage regulator. The unit 

is then allowed to gradually bleed down. When the low air alarm is activated, the pressure on the 

gauge is recorded. This procedure is repeated six times. The average of the six readings is calculated 

and recorded.

The test requirement was identified on the label

as 33%-37% of its 4500 psi remaining rated 

service time. Could not test electrical alarm due 

to disconnected wire from the MMR. 

 Electrical Bell 

Run # Alarm Point (psi) Alarm Point (psi)

1 - 1585

2 - 1553

3 - 1562

4 - 1585

5 - 1554

6 - 1581

 Average: - 1570 PASS

Table 2. National Fire Protection Association (NFPA) Test (in accordance with NFPA 1981, 2013 Edition). 

NFPA Test Description of Results PASS/

FAIL 

NFPA Airflow Performance Test - NFPA 1981 (2013 Edition) Reference: Chapter 8, Performance 

Requirements, Sec. 8-1.1

Requirement: 

SCBA shall be tested for airflow performance as specified in Section 8.1, Airflow Performance Test, 

and the SCBA facepiece pressure shall not be less than 0.0 in (0.0 mm) water column and not greater 

than 31⁄2 in (89 mm) water column above ambient pressure from the time the test begins until the 

time the test is concluded.

Procedure: 

The required equipment specified in the NFPA standards were used to conduct the tests on this 

unit. A pressure tap in the head is connected to a transducer which in turn is connected to a flatbed 

chart recorder for determining the pressure in the facepiece.

The SCBA passed this test. 

Maximum Facepiece Pressure: (inches of water 

column) = 2.55 

Minimum Facepiece Pressure: (inches of water 

column) = 0.17

PASS

PASS
 

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Disposition of SCBA

At all times, except for testing on the dates of June 30, 2022, and July 12, 2022, the SCBA unit was securely

stored in Lab H1513 at the NIOSH facility in Morgantown, West Virginia.

Synopsis of Findings

The SCBA unit inspected and evaluated by NPPTL was identified as an MSA Model G1, 30-minute, 4500 psi unit 

with NIOSH Approval Number TC-13F-0786CBRN. The firefighter was wearing the unit when the event occurred. 

The corresponding facepiece and cylinder were provided with the unit. The testing team determined to use the 

replacement cylinder provided by the Lower Merion Fire Department due to damage to the cylinder involved in 

the event. Overall, the SCBA was in good condition. The NFPA approval label was present and readable. The 

mechanical alarm system functioned as designed during the inspection and during the remaining service life 

indicator testing completed on June 30, 2022. However, it seems as though the electrical system was not 

working properly since the PASS would not respond to “shaking the unit” to deactivate the alarm once sounded

while idle and with a full cylinder. This may be due to the electrical wire being disconnected from the MMR. For 

this reason, the testing team was not able to test the electrical system during the Remaining Service Life 

Indicator Test NIOSH Standard Testing Procedure Number 124. The unit passed all other NIOSH tests. The unit 

was tested on the NFPA “Airflow Performance” test on July 12, 2022 and met all requirements.

The information obtained during this investigation does not suggest that the components tested contributed to 

the fatality. The SCBA was returned to the shipping container to be shipped back to the Lower Merion Fire 

Department.

CASE Conclusion

No evidence was identified to suggest that the SCBA unit inspected and evaluated contributed to the fatality.

NIOSH determined that there was no need for corrective action with regards to the approval holder or end 

users of the SCBA manufactured under the approval number granted to this product.

Actions to be Taken by the Fire Departments with SCBAs Involved 

in an Incident

• Any SCBA unit involved in an incident may not be placed back in service until the SCBA has been

repaired, tested, cleaned, and any damaged components replaced and inspected by a qualified

service technician, including such testing and other maintenance activities as prescribed by the 

schedule from the SCBA approval holder.

• All SCBA units, even those not involved in an incident, must undergo a flow test on at least an annual

basis.
 

TN-25965 Lower Merion Fire Department, PA 9 

Actions PPE Users, Selectors, and Purchasers May Take to Further

Protect Themselves and Others from Hazards

• Sign up for NPPTL’s Listserv to receive email notifications relevant to PPE. 

To request additional information about this report, contact NPPTL at ppeconcerns@cdc.gov, and reference 

NIOSH Task Number 25965 in your request. 

For more information related to personal protective equipment, visit the NIOSH website

https://www.cdc.gov/niosh/npptl/

To receive documents or other information about occupational safety and health topics, contact NIOSH:

Telephone: 1–800–CDC–INFO (1–800–232–4636) 

TTY: 1–888–232–6348

CDC INFO: www.cdc.gov/info

Or visit the NIOSH website at https://www.cdc.gov/niosh/

For a monthly update on news at NIOSH, subscribe to NIOSH eNews by visiting 

https://www.cdc.gov/niosh/eNews/
 

TN-25965 Lower Merion Fire Department, PA 10

Appendix 1: Acronyms and Abbreviations

CBRN Chemical, Biological, Radiological, and Nuclear

CDC Centers for Disease Control and Prevention

CFR Code of Federal Regulations

CGA Compressed Gas Association

DOT Department of Transportation

FD Fire Department

HUD Heads-Up Display

kg-m/min Kilogram Meter per Minute

L/min Liters per Minute

M/N Manufacturer Number

MFG Manufacturing Date

mm Millimeters

mmH2O Millimeters of Water

MMR Mask-Mounted Regulator

MSA Mine Safety Appliances

NFPA National Fire Protection Association

NIOSH National Institute for Occupational Safety and Health

NPPTL National Personal Protective Technology Laboratory

P/N Part Number

PASS Personal Alert Safety System

PSI Pounds per Square Inch

PSIG Pounds per Square Inch Gauge

RFID Radio Frequency Identification

RIC/UAC Rapid Intervention Crew/Universal Air Connection

RPM Revolutions per minute

SCBA Self-Contained Breathing Apparatus

SEI Safety Equipment Institute

STP Standard Testing Procedure
 

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Appendix 2: Photographs to Support Inspection Findings for the 

SCBA 

List of Figures

Figure 1: SCBA as-received .........................................................................................................................................2

Figure 2: SCBA as-received out of packaging .............................................................................................................3

Figure 3: Front of facepiece..................................................................................................................................... 12

Figure 4: Inside facepiece and HUD......................................................................................................................... 12

Figure 5: Facepiece head harness and straps.......................................................................................................... 13

Figure 6: Bottom left lug broken on facepiece........................................................................................................ 13

Figure 7: Mask-mounted regulator with HUD wire not connected ........................................................................ 14

Figure 8: Inside of mask-mounted regulator........................................................................................................... 14

Figure 9: Mask-mounted regulator and medium-pressure hose connected to SCBA ............................................ 15

Figure 10: Medium-pressure hose in protective sleeve.......................................................................................... 15

Figure 11: Pressure reducer, RIC/UAC with primary low-pressure warning device (bell) ...................................... 16

Figure 12: Bottom view of pressure reducer assembly........................................................................................... 16

Figure 13: Front of PASS control module ................................................................................................................ 17

Figure 14: Protective boot of PASS control module................................................................................................ 17

Figure 15: Labeling on PASS control module........................................................................................................... 18

Figure 16: High-pressure hose and cylinder attachment........................................................................................ 18

Figure 17: Top view of high-pressure hose ............................................................................................................. 19

Figure 18: RIC/UAC rubber dust cap........................................................................................................................ 19

Figure 19: RIC/UAC fitting........................................................................................................................................ 20

Figure 20: PASS power module SEI label................................................................................................................. 20

Figure 21: Power module ........................................................................................................................................ 21

Figure 22: Battery as received................................................................................................................................. 21

Figure 23: Battery out of packaging ........................................................................................................................ 22

Figure 24: Overview of backplate, straps, and buckles........................................................................................... 22

Figure 25: Waist belt not attached to backplate..................................................................................................... 23

Figure 26: Backplate with cylinder holder............................................................................................................... 23

Figure 27: Top view of cylinder with labeling.......................................................................................................... 24

Figure 28: Top view of cylinder with labeling.......................................................................................................... 24

Figure 30: Cylinder valve and rubber boot.............................................................................................................. 25

Figure 32: Top view of cylinder with labeling.......................................................................................................... 26

Figure 31: Threaded CGA quick-connect adapter attached to cylinder.................................................................. 26
 

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Figure 4: Inside facepiece and HUD

Figure 3: Front of facepiece
 

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Figure 5: Facepiece head harness and straps

Figure 6: Bottom left lug broken on facepiece
 

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Figure 7: Mask-mounted regulator with HUD wire not connected

Figure 8: Inside of mask-mounted regulator
 

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Figure 9: Mask-mounted regulator and medium-pressure hose connected to SCBA

Figure 10: Medium-pressure hose in protective sleeve
 

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Figure 11: Pressure reducer, RIC/UAC with primary low-pressure warning device (bell)

Figure 12: Bottom view of pressure reducer assembly
 

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Figure 13: Front of PASS control module

Figure 14: Protective boot of PASS control module
 

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Figure 15: Labeling on PASS control module

Figure 16: High-pressure hose and cylinder attachment
 

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Figure 17: Top view of high-pressure hose

Figure 18: RIC/UAC rubber dust cap
 

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Figure 19: RIC/UAC fitting

Figure 20: PASS power module SEI label
 

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Figure 21: Power module 

Figure 22: Battery as received
 

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Figure 23: Battery out of packaging

Figure 24: Overview of backplate, straps, and buckles
 

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Figure 25: Waist belt not attached to backplate

Figure 26: Backplate with cylinder holder
 

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Figure 27: Top view of cylinder with labeling

Figure 28: Top view of cylinder with labeling
 

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Figure 29: Cylinder gauge

Figure 29: Cylinder valve and rubber boot
 

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Figure 30: Top view of cylinder with labeling

Figure 31: Threaded CGA quick-connect adapter attached to cylinder
 

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Disclaimer 

These evaluations are done to determine if the SCBA was a contributing factor to the incident. A number of

performance tests are selected from the complete list of 42 CFR Part 84 requirements and each respirator is

tested in its “as received” condition to determine its conformance to those performance requirements.

In order to gain additional information about its overall performance, each respirator may also be subjected

to other recognized test parameters, such as National Fire Protection Association (NFPA) consensus

standards. While the test results give an indication of the respirator’s conformance to the NFPA

approval requirements, NIOSH does not actively correlate the test results from its NFPA test equipment

with those of certification organizations which list NFPA-compliant products. Thus, the NFPA test results

are provided for information purposes only.

Selected tests are conducted only after it has been determined that each respirator is in a condition that

is safe to be pressurized, handled, and tested. Respirators whose condition has deteriorated to the point

where the health and safety of NIOSH personnel and/or property is at risk will not be tested.

Suggested Citation

NIOSH [2022]. PPE CASE: Evaluation of Self-Contained Breathing Apparatus Involved in a Fatality While 

Operating at a Structure Fire: Lower Merion Fire Department, PA, Request for a MSA Model G1, 30-minute, 

4500 psi unit. By Andrews, A, Tarley, J. Morgantown, WV U.S. Department of Health and Human Services, 

Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, NPPTL 

Report Number TN-25965.