Approvals: First Level Second Level Third Level Fourth Level

National Institute for Occupational Safety and Health

National Personal Protective Technology Laboratory

P.O. Box 18070

Pittsburgh, PA 15236

Procedure No. TEB-CCER-STP-0614 Revision: 0.0 Date: 7 April 2014

ASSESSMENT OF STRESSORS DURING CLOSED-CIRCUIT ESCAPE RESPIRATORS (CCERs)

TESTS WITH HUMAN SUBJECT: CAPACITY, PERFORMANCE AND WEARABILITY

1. PURPOSE

This procedure describes the methods for assessing stressors during CCER tests with human 

subjects to ensure that Closed-Circuit Escape Respirators (CCER) submitted for Approval, 

Extension of Approval, or examined during Certified Product Audits, meet the certification 

standards as set forth in Sections 84.303, 84.304 (a) (4), 84.305 (a) (3), and 84.306 of Subpart 

O−Closed Circuit Escape Respirators updated requirements to 42 CFR, Part 84, Volume 60, 

Number 110, June 8, 1995 as published in Federal Register / Vol. 77, No. 46 / Thursday, March 

8, 2012 / Rules and Regulations pp. 14168-14197.

2. GENERAL

This standard test procedure (STP) describes the protocol for assessing stressors monitored during 

human capacity, human performance, and wearability tests in sufficient detail such that a person 

knowledgeable in the appropriate technical field can conduct the assessment of stressors 

associated with human subject testing of closed circuit escape respirators (CCER).

3. EQUIPMENT

3.1 Specific equipment requirements are found in the standard test procedures for 

wearability, human-subject performance and human-subject capacity.

3.1.1 TEB-CCER-STP-0610 for wearability of closed-circuit escape respirators

3.1.2 TEB-CCER-STP-0613 for performance test of closed-circuit escape respirators 

(CCER) with human subjects on treadmill

3.1.3 TEB-CCER-STP-0612 for capacity test of closed-circuit escape respirators 

(CCER) with human subjects on treadmill

4. PROCEDURE REQUIREMENTS AND CONDITIONS

4.1. During human subject tests the stressors in Table 1 are monitored on a breath-by-breath 

basis and continuously recorded using LabView software and/or a strip chart recorder. 

(See Appendices).

4.2. Prior to performing CCER tests with human subjects, perform the calculations specified 

in the standard test procedure for capacity and performance using current Breathing and 
Procedure No. TEB-CCER-STP-0614 Revision: 0.0 Date: 7 April 2014 Page 2 of 6

Metabolic Simulator (BMS) test data upon the same make and model CCER. All tests 

utilizing the breathing and metabolic simulator (BMS) required for certification shall

have been successfully completed with passing results before performing tests involving 

human subjects.

5. PROCEDURES

5.1. During the tests with human subjects, the %CO2, %O2, Inhalation/Exhalation Pressure, 

and wet bulb temperature is continuously recorded on a multi-channel recorder and/or 

LabView data collection system. Beginning with the first minute and over each minute 

during the test:

5.1.1 The minute average for each stressor is estimated during the test.

5.1.2 The cumulative average for each stressor is estimated during the test.

5.2. Calculation of average inhaled gas concentrations from end-of-inhalation gas 

concentrations:

5.2.1. From the continuous chart recording or LabView display, identify the maximum

end-of-inhalation % CO2 concentration and record in the data sheet under 

“Maximum Inhaled CO2 %”

5.2.2. Estimate the minute average of the inhaled % CO2 peaks for the one-minute 

interval and record on the data sheet under “Minute Average CO2 %”.

5.2.3. From the continuous chart recording or LabView display, identify the minimum 

end of inhalation oxygen concentration and record in the data sheet under 

“Minimum Inhaled O2%”.

5.2.4. Estimate the minute average of the inhaled % O2 peaks for the one minute 

interval and record on the data sheet under “Minute Average O2 %”.

5.2.5. Complete mathematical calculations to determine the running range average for 

% CO2 and % O2. Use the following equation:

Range average = [current overall average x current elapsed time] +new minute average

[current elapsed time + 1 minute]

5.3. Calculation of average inhalation and exhalation breathing pressure

5.3.1. From the continuous chart recording or LabView display, identify the minimum 

inhalation pressure for the one-minute interval, and record in the data sheet under 

“Minute Minimum Inhaled Pressure”.

5.3.2. From the continuous chart recording or LabView display, identify the maximum 

exhalation pressure for the one-minute interval, and record in the data sheet

under “Minute Maximum Exhaled Pressure”.
Procedure No. TEB-CCER-STP-0614 Revision: 0.0 Date: 7 April 2014 Page 3 of 6

5.3.3. Calculate the range excursion for the minute in question using the following 

equation.

∆P=│maximum exhaled pressure - minimum inhaled pressure│

5.4. Calculation of average inhalation wet-bulb temperature 

5.4.1. From the continuous chart recording or LabView display, identify peak that 

represents the maximum inhalation wet-bulb temperature for the one-minute 

interval.

5.4.2. Estimate the minute average for the maxima in the proper one-minute interval 

graphically, and record in the data sheet under “Minute Inhaled Wet Bulb 

Temperature” at the proper minute. 

5.4.3. Calculate the Running Range Average Wet Bulb Temperature and record on the 

data sheet. Use the following formula:

Range average = [current overall average x current elapsed time] +new minute average

[current elapsed time + 1 minute]

6. PASS/FAIL CRITERIA

6.1. Refer to the standard test procedure for the specific test being performed and Table 1.

Table 1: Monitored Stressors and their Acceptable Ranges

Stressor Acceptable Range

Operating Average

Acceptable Range

Excursion

Average inhaled CO2 <1.5% ≤4%

Average inhaled O2

>19.5% ≥15%

Peak Breathing Pressures ∆P ≤ 200 mm H2O -300 ≤ ∆P ≤ 200 mm H2O

Wet-bulb temperature <43 ̊C ≤50 ̊C
Procedure No. TEB-CCER-STP-0614 Revision: 0.0 Date: 7 April 2014 Page 4 of 6

7. RECORDS AND TEST SHEETS:

Data Sheet for Average Inhaled Carbon Dioxide and Average Inhaled Oxygen 

Time Maximum 

Inhaled 

CO2% 

Minute 

Average CO2 

%

Running Range 

Average CO2 %

Minimum 

Inhaled 

O2%

Minute 

Average O2

%

Running Range 

Average O2 %

Minute Limit= ≤4% Limit = 4% Limit ≤ 1.5% at 

test end

Limit= 

≥15%

Limit = 

15%

Limit = >19.5%

at test end

1

2

3

4

5

6

7

8

9

10

Add rows 

as needed

Test end

Data Sheet for Peak Breathing Pressures

Time Minute 

Minimum 

Inhaled 

Pressure

Minute 

Maximum 

Exhaled 

Pressure

Running 

Range 

Excursion

Minute Limit ≥ -300 

mm H2O

Limit ≤ 

200 mm 

H2O

Limit

│∆Pressure│

≤ 200 mm 

H2O

1

2

3

4

5

6

7

8

9

10

Add rows as 

needed

Test end
Procedure No. TEB-CCER-STP-0614 Revision: 0.0 Date: 7 April 2014 Page 5 of 6

Data Sheet for Wet-Bulb Temperature

Time Minute 

Inhaled Wet 

Bulb 

Temperature

Running 

Range 

Average 

Wet Bulb 

Temperature

Minute Limit ≤ 

50°C

Limit ≤ 

43°C at test 

end

1

2

3

4

5

6

7

8

9

10

Add rows as 

needed

Test end

8. ATTACHMENTS

None
Procedure No. TEB-CCER-STP-0614 Revision: 0.0 Date: 7 April 2014 Page 6 of 6

Revision History

Revision Date Reason for Revision

0.0 Initial record

1.0 18 August 2011 Review

2.0 20 August 2012 Administrative changes – changed document number

3.0 10 April 2012 Administrative changes were made to include information from the 

release of the proposed rule.

4.0 21 May 213 TEB Changes