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 and Conducting Overhaul 

Watertown Fire Department Request for a Scott® Safety Air-Pak Model X3

At the request of the Watertown Fire Department, NIOSH’s National Personal 

Protective Technology Laboratory (NPPTL) inspected and evaluated the SelfContained Breathing Apparatus (SCBA) involved in a fatal event at a structure fire. 

This report provides a summary of NPPTL’s inspection and evaluation methods, as 

well as findings, for an SCBA that was being used by a fire fighter while operating 

at a structure fire and conducting overhaul. The SCBA used was a Scott® Safety 

Air-Pak Model X3, 30-minute, 4500 psi unit. The Watertown Fire Department was 

advised that NIOSH NPPTL would provide a written report of the investigation and 

any applicable test results. 

What NIOSH Did to Protect the Worker

Upon receipt of the SCBA, NPPTL managed the custody of evidence throughout the 

inspection and evaluation process at its Morgantown, West Virginia facility. NPPTL 

staff inspected all of the SCBA components and documented their findings with 

written and photographic evidence. NPPTL also tested the SCBA to determine 

conformance to NIOSH’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) Air Flow Performance requirements of NFPA 1981, Standard on 

Open-Circuit Self-Contained Breathing Apparatus for the Fire Service, 2013 Edition. If the inspection or evaluation data 

suggested that the SCBA unit may have contributed to the fatality, NPPTL would have engaged in corrective action to ensure 

that no other users of the product would experience a similar incident. In this case, no such corrective action was necessary. 

NPPTL then managed the disposition of the SCBA until it was returned to the fire department. 

NIOSH evaluated an SCBA 

involved in a fatal event 

while the fire fighter 

operated at a structure fire 

and conducted overhaul.

The SCBA was not found to 

contribute to the incident. 

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.
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 2 

Chain of Custody

The SCBA and compressed air cylinder, were delivered via UPS ground in a cardboard box to Lab H1513 at the NIOSH

facility in Morgantown, West Virginia on September 27, 2018. The SCBA unit remained in secured storage in Lab 

H1513 throughout the inspection and testing process. 

SCBA Inspection

On October 11, 2018, NPPTL employees Matt Duling and Jay Tarley inspected the SCBA unit. The SCBA was identified

as belonging to the Watertown Fire Department and was visually examined, component by component, in the

condition received to determine the conformance of the unit to the NIOSH-approved configuration. The unit was 

identified as the Scott® Safety Air-Pak Model X3, 30-minute, 4500 psi unit, with NIOSH Approval Number TC-13F0713CBRN. 

As Received 

• SCBA was delivered by UPS ground in a cardboard box to Lab H1513

• SCBA was in good shape

• A cylinder was included and was empty

• A mask was included

• The donning switch was on, with regulator intact

• Bypass was half open

Figure 1: SCBA as received 
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 3 

Figure 2: SCBA as received
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 4 

Components and Observations for SCBA (“right” or “left” are from the user’s perspective) (see Figures in 

Appendix)

Facepiece AV 3000 (Figures 3-5) 

• Facepiece seal P/N: 31001740; Large; MFG date: 

01/2016

• Nosecup P/N: 201128; Size: Large; MFG date: 4th Q 

2015 

• Retaining ring top MFG date: 10/2015; P/N: 

31002809; bottom MFG date 2/2016, P/N 

31002810, Lot # 021016, FT1006

• Lens P/N: 805337-13/-33/-36; MFG date: 03/2014

• Overall condition was good, with minimal scratches

• Lens was good, with minimal scratches

• Hairnet condition was good, but dirty

• Hairnet straps were good, straps moved freely and 

held in place by buckle, held securely to facepiece

• Attachment points for straps were good

• The facepiece seal was in good condition

• Regulator interface area was in good condition

Mask Mounted Regulator (MMR) (Figures 6, 7) 

• Vibralert with Heads-Up Display (HUD) 

• Regulator assembly P/N, S/N and MFG date: 

present P/N 200077-58, S/N 115S1619010318, 

2013 LH X3 CGA, MFG date 05/11/16

• Other markings; 1-13, 1-16, 7-14 and 10-15 

scribed on inside flange FT 837, A2Q 16

• Overall condition was good

• Outer case was good and front label was good

• Donning switch was on

• Bypass found halfway open, bypass knob was good

• Sealing area was good with no signs of fraying 

around the edge, had minimal scratches

• Locking assembly functioned

• HUD fully intact

Low Pressure Regulator Hose (Figures 8, 9) 

• P/N: 31001446

• Overall condition was good 

• No quick disconnect

Pressure Reducer Assembly (Figures 10 -12)

• P/N: 201030-02 

• S/N 115S1619011475

• MFG date: 5/11/16 

• Overall condition was good, slightly dusty

• All airline connections were secure with no sign of 

heat damage

High Pressure Hose and Cylinder Attachment (Figures 13 

- 15) 

• Overall condition was good. No signs of heat 

damage on inside of high-pressure line attachment 

rubber cover. 

• Cylinder attachment threads were good and O-ring 

in place 

• RIC/UAC system connector markings: not visible

• RIC/UAC system connector cover in good condition

• Additional marking on side of high pressure 

attachment: FT 988

PASS Console Assembly (Figures 16, 17) 

• X3 console assembly, PASS 4500, 1/3

• Scott label: P/N 201110-11, S/N 115S1618013477, 

MFG Date 5/4/16

• Overall condition was good, slightly dirty

• Lines in good shape—pressure/electrical

• Gauge lens was good and readable

• Attachment not present 

• SEI label present, 2013 edition

PASS Control Module with PAK-Alert (Figures 18 - 20) 

• Scott P/N: 201160-02 with paktracker 

• MFG date: 5/3/2016

• Overall condition was good, slightly dirty

• Held securely to backframe

• Wire connection connected to PASS device

• Wire held secure to backframe and connected to 

console assembly

Backframe Assembly (Figures 21, 22) 

• SEI label P/N 201100-001, S/N 115S1619013089, 

MFG date 5/11/16

• NIOSH label TC-13F-0713CBRN

• Other marking: Two additional labels: ID00285613, 

WTN C201

• Overall condition was good, no bends or cracks in 

wire frame, or plate

• Shoulder straps were attached to the frame

• Cylinder strap latch was in good condition, 

functional

Straps and Buckles (Figures 23, 24) 

• Overall strap condition was good

• Both shoulder straps were attached at the top of 

the backframe 

• Hose lines and wires passed through shoulder 

straps

• All adjustable buckles moved and held in place
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 5 

• Waist area buckle latched and released

• Lumbar strap was in good condition; no fraying 

showing

Compressed Air Cylinder and Cylinder Valve Assembly

(Figures 25 - 27) 

Minute Duration: 30-minute

DOT –Number: DOT-ST 10915-4500

TC-3CCM-310 

OK 550092

REE: 76

Scott P/N: 10009671 

Scott logo visible Luxfer L45M-018

MFG date: 3/2016 4500 PSIG

• Overall condition was good as there were no

surface scratches or dirt present (minimal)

• Gauge was readable 

• Threads were clean 

• As received, cylinder valve was fully closed with no 

air remaining

• Rubber bumper at base on cylinder valve was in 

good condition

• Rehydro label was present: 3/16 

• S/N for assembly/cylinder 115S1617079169

• On Stem: 115A1617078920
 

 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 10 

SCBA Testing

The SCBA unit was tested using the six NIOSH test methods and one NFPA test method as described in Table 1.

Table 1. Summary of results from testing SCBA

NIOSH Tests Description of Results PASS/

FAIL

Positive Pressure Test - NIOSH Standard Test 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-liter 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 a computer-based recorder for determining the pressure in the facepiece.

The unit met the test requirement. The 

inhalation breathing resistance did not 

become negative during the test. 

*The PASS and HUD did not function.

Inhalation Breathing Resistance: (inches 

of water column) = 0.4 PASS

Rated Service Time Test - NIOSH Standard Test 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 a computer-based recorder 

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 SCBA did not go negative on 

inhalation; therefore, maintained positive 

pressure in the facepiece. The measured 

service time (adjusted to correspond with 

the recorded breathing cycles) was more 

than the rated service time of 30

minutes. The PASS unit did not function.

Measured Service Time: 

32 Minutes 68 Seconds

PASS
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 7

Static Pressure Test - NIOSH Standard Test 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) = 1.10 PASS 

Gas Flow Test – NIOSH Standard Test 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 Air Flow (liters per min.) 

4500 psig 470 lpm

500 psig 606 lpm

PASS 

PASS
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 8 

Exhalation Resistance Test - NIOSH Standard Test 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 head form. A probe in the head form is 

connected to a slant manometer for measuring exhalation breathing resistance. The air 

flow 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) = 1.94

Static Pressure: (inches of water

column) = 1.01

Difference: (inches of water column) = 

0.93 PASS

Remaining Service Life Indicator Test - NIOSH Standard Test 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 remaining 

rated service time. 

Electric Vibralert

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

1 NA 1540

2 NA 1550

3 NA 1550

4 NA 1540

5 NA 1540

6 NA 1540 

Average 0 1543

FAIL

PASS

 
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 9 

National Fire Protection Association (NFPA) Test (in accordance with NFPA 1981, 2013 Edition):

NFPA Test Description of Results PASS/

FAIL 

NFPA Air Flow Performance Test—NFPA 1981 (2013 Edition) Reference: Chapter 8, 

Performance Requirements, Section 8-1.1

Requirement: 

SCBA shall be tested for air flow performance as specified in Section 8.1, Air flow

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 equipment specified in the NFPA standards will be 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 the pressure portion of 

this test. PASS and HUD systems were 

not functional which caused the unit to 

fail the test.

Maximum Facepiece Pressure: (inches 

of water column) = 2.2 

Minimum Facepiece Pressure: (inches 

of water column) = 0.7 

FAIL
 

 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 10 

Disposition of SCBA

Following testing on October 12, 2018, the SCBA was returned to secure storage in Lab H1513 at the NIOSH

facility in Morgantown, West Virginia. 

Synopsis of Findings

The SCBA unit inspected and evaluated by NPPTL was a Scott® Safety Air-Pak Model X3, 30-minute, 4500 psi

unit with NIOSH Approval Number TC-13F-0713CBRN. A facepiece was provided with the unit. A cylinder was 

provided by the fire department for testing. Overall, the SCBA was in good condition. The NFPA approval

label was present and readable. The PASS, HUD, and alarm systems did not function. 

The unit did not pass the electronic part of the Remaining Service Life Indicator Test - NIOSH Standard Test 

Procedure Number 124, 42 CFR Part 84 Reference: Subpart H, § 84.83 (f) and Subpart G, § 84.63 (c) due to the 

HUD and electronic warning devices not working. The SCBA did meet the requirements of the NIOSH Positive 

Pressure Test (NIOSH Standard Test Procedure 120, 42 CFR Part 84 Reference: Subpart H, 84.70 (a)(2)(ii)) and 

the other NIOSH tests. It did not meet the requirements of the NFPA “Airflow Performance” test due to the 

HUD and PASS not operating.

In light of the information obtained during this investigation, NIOSH NPPTL suggests that the unit be sent back 

to the manufacturer to fix the HUD and electrical safety components. The SCBA was returned to the shipping 

container to be shipped back to the Watertown Fire Department. 

If this unit is to be placed back in service, the SCBA must be 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 manufacturer. Typically, a flow test is 

required on at least an annual basis.

CASE Conclusion

This SCBA unit failed to pass all tests conducted by NIOSH. Per guidance in the Synopsis of Findings, it is 

recommended that the end user send the unit back to the manufacturer. 

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 manufacturer. 

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

basis. 
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 11 

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 22547 in your request. 

For more information related to personal protective equipment, visit the NIOSH NPPTL 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-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 12 

Appendix: Photographs to Support Inspection Findings for SCBA

List of Figures

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

Figure 2: SCBA as received .........................................................................................................................................3 

Figure 3: Front of facepiece..................................................................................................................................... 13

Figure 4: Inside of facepiece.................................................................................................................................... 13

Figure 5: Facepiece headnet.................................................................................................................................... 14 

Figure 6: Mask mounted regulator.......................................................................................................................... 14

Figure 7: Inside seal of mask mounted regulator and HUD .................................................................................... 15 

Figure 8: Low pressure hose.................................................................................................................................... 15 

Figure 9: Low pressure manufacturer and part number......................................................................................... 16 

Figure 10: Pressure reducer, top view..................................................................................................................... 16 

Figure 11: Pressure reducer, label........................................................................................................................... 17 

Figure 12: Pressure reducer, low pressure connect................................................................................................ 17 

Figure 13: Cylinder attachment, RIC UAC connector .............................................................................................. 18 

Figure 14: Cylinder attachment threads and O-ring................................................................................................ 18 

Figure 15: RIC UAC with dust cover removed ......................................................................................................... 19 

Figure 16: PASS control console ............................................................................................................................. 19

Figure 17: SEI label on back of PASS control console, 2013 edition ....................................................................... 20

Figure 18: PASS control module with sticker .......................................................................................................... 20

Figure 19: Manufacturer sticker on PASS Control module...................................................................................... 21

Figure 20: Wire connections to PASS control module............................................................................................. 21

Figure 21: Backframe .............................................................................................................................................. 22 

Figure 22: Cylinder attachment............................................................................................................................... 23 

Figure 23: Straps and buckles on pack frame.......................................................................................................... 24 

Figure 24: Shoulder strap attachments................................................................................................................... 24 

Figure 25: Air tank ................................................................................................................................................... 25 

Figure 26: Gauge, threads, cylinder valve and rubber bumper............................................................................... 25 

Figure 27: Manufacturer’s label on stem and bottle....................................................................................................... 26 
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 13 

Figure 3: Front of facepiece

Figure 4: Inside of facepiece
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 14 

Figure 5: Facepiece hairnet

Figure 6: Mask mounted regulator
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 15 

Figure 7: Inside seal of mask mounted regulator and HUD

Figure 8: Low pressure hose
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 16 

Figure 9: Low pressure hose manufacturer and part number

Figure 10: Pressure reducer, top view
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 17 

Figure 11: Pressure reducer, label

Figure 12: Pressure reducer, low pressure connection 
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 18 

Figure 13: Cylinder attachment and RIC UAC connector

Figure 14: Cylinder attachment threads and O-ring
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 19 

Figure 15: RIC UAC dust cover removed

Figure 16: PASS control console
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 20 

Figure 17: SEI label on back of PASS control console, 2013 edition 

Figure 18: PASS control module with sticker
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 21 

Figure 19: Manufacturer sticker on PASS control module

Figure 20: Wire connections to PASS control module
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 22 

Figure 21: Backframe
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 23 

Figure 22: Cylinder attachment 
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 24 

Figure 23: Straps and buckles on pack frame

Figure 24: Shoulder strap attachments
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 25 

Figure 25: Compressed air cylinder

Figure 26: Gauge, threads, cylinder valve, and rubber bumper
 TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 26 

Figure 27: Manufacturer’s labels on stem and bottle
TN-22547 Watertown Fire Department, Massachusetts – Status Investigation Report 27

Disclaimer 

The purpose of this effort was to determine the conformance of a respirator to the NIOSH approval 

requirements found in Title 42, Code of Federal Regulations, Part 84. A number of performance tests are 

selected from the complete list of Part 84 requirements and each respirator is tested in its “as received” 

condition to determine its conformance to those performance requirements. Each respirator is also 

inspected to determine its conformance to the quality assurance documentation on file at NIOSH. 

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.