Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

National Institute for Occupational Safety and Health 

National Personal Protective Technology Laboratory 

P.O. Box 18070 

Pittsburgh, PA 15236

Procedure No. TEB-APR-STP-0513-CBRN Revision: 0.1 Date: 9 February 2009

DETERMINATION OF CBRN ACID GASES (HYDROGEN CYANIDE) 

SERVICE-LIFE TEST, LOOSE-FITTING POWERED AIR-PURIFYING 

RESPIRATORS (PAPR) STANDARD TEST PROCEDURE (STP) 

1. PURPOSE

This test establishes the procedure for ensuring that the level of protection provided by the CBRN 

Acid Gases (Hydrogen Cyanide) Service Life Test, Loose-fitting Powered Air Purifying 

Respirators (PAPR) Standard Test Procedure submitted for Approval, Extension of Approval, or 

examined during Certified Product Audits, meet the minimum certification standards set forth in 

42 CFR Part 84, Subpart G, 84.63(a)(c)(d); Volume 60, Number 110, June 8, 1995 and the 

Statement of Standard for Chemical, Biological, Radiological, and Nuclear (CBRN) Powered Air 

Purifying Respirator(PAPR). 

2. GENERAL

This STP describes the Determination of CBRN Acid Gases (Hydrogen Cyanide) Service Life 

Test, Loose-fitting Powered Air-Purifying Respirators (PAPR) Standard Test Procedure test in 

sufficient detail that a person knowledgeable in the appropriate technical field can select 

equipment with the necessary resolution, conduct the test, and determine whether or not the 

product passes the test.

3. EQUIPMENT AND MATERIAL

3.1. The list of necessary test equipment and materials follows: 

3.1.1. Miller Nelson Research Model 401 Flow-Temperature-Humidity Control System 

or equivalent. This system is an automated system to control the airflow, 

temperature, and humidity of an air supply for an operating system. Laboratory 

air and distilled water are supplied to the unit. The unit output is air of the 

variable volume/flow dependant on the size of unit (10% of max flow to max 

flow in liters per minute (Lpm)  2%), and relative humidity (10%–98%  3%) 

and temperature (20oC–30o 0

C  0.3%). 

3.1.2. EdgeTech Dew Prime II Hygrometer, Model 2000 or equivalent. A microprocessor based programmable chilled mirror dew point hygrometer . The 

hygrometer uses the dew point and ambient temperature to calculate the relative 

humidity. Ambient temperature range is: -50oC to 130oC ± 0.2oC; relative 

humidity is 1% to 95% ± 0.5%. 

Approvals: First Level Second Level Third Level Fourth Level 

 
Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Procedure No. TEB-APR-STP-0513-CBRN Revision: 0.1 Date: 9 February 2009 Page 2 of 10 

3.1.3. Labview software developed for NIOSH Service Life Testing. 

3.1.4. California Analytical Instruments, Model 1314 Photoacoustic Multigas Monitor 

with UA0980 optical filter or equivalent. This monitor uses photoacoustic 

infrared detection to measure gases that absorb infrared light. A filter is used to 

select the wavelength specific for the gas being detected. Range for hydrogen 

cyanide is 8000 to 0.8 ppm ± 0.08 ppm. 

3.1.5. Gas Chromatograph, Shimadzu, Model 14A with Flame Ionization Detectors or 

equivalent. 

3.1.6. Mass Flow Controller, Brooks Instruments, Model 5851. Variable flow rate 

depending on use. 

3.1.7. Read out and Control Electronics, Brooks Instruments, Model 0154. Power 

supply and controller for the Brooks Mass Flow Controller or equivalent. The 

flow controllers are an integrally mounted control valve module with which 

stable gas flows can be achieved. Various flow rates are used with an accuracy of 

 0.7 % of rate and  0.2 % full scale. 

 

3.1.8. Dry Test Meter, American Meter Company, model and size depending on air 

flow to be measured. Must have NIST traceable calibration certificate. 

3.1.9. Certified cylinders of 5 ppm and 500 ppm hydrogen cyanide, balance gas 

Nitrogen or hydrogen cyanide permeation tubes that are certified to NIST 

standard. 

3.1.10. Kin-Tek 491MB Basic Gas Standards Generator with cyanogen permeation 

tubes that are certified to NIST standard. 

3.1.11. Hydrogen Cyanide cylinders, 2% hydrogen cyanide, balance gas of nitrogen. 

3.2. Test fixture for mounting cartridges. 

3.3. The test chamber consisting of an air tight box with door opening lined with gasket 

material. Two fittings located on the test chamber for the introduction of the test 

concentration and for the exit of the test fixture. This fixture is not commercially 

available 

3.4. Airflow measurement equipment as described in standard test procedure RCT-APR00012. 

4. TESTING REQUIREMENTS AND CONDITIONS

4.1. Prior to beginning any testing, all measuring equipment to be used must have been 

calibrated in accordance with the manufacturer's calibration procedure and schedule. At a 

minimum, all measuring equipment utilized for this testing must have been calibrated 

within the preceding 12 months using a method traceable to the National Institute of 
Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Procedure No. TEB-APR-STP-0513-CBRN Revision: 0.1 Date: 9 February 2009 Page 3 of 10 

Standards and Technology (NIST). 

4.2. Any laboratory using this procedure to supply certification test data to NIOSH will be 

subject to the provisions of the NIOSH Supplier Qualification Program (SQP). This 

program is based on the tenets of ISO/IEC 17025, the NIOSH Manual of Analytical 

Methods and other NIOSH guidelines. An initial complete quality system audit and 

follow on audits are requirements of the program. Additional details of the Program and 

its requirements can be obtained directly from the institute. 

4.3. Precision and accuracy (P&A) must be determined for each instrument in accordance 

with laboratory procedures and NIOSH/NPPTL guidance. Sound practice requires, under 

NIOSH Manual of Analytical Methods, demonstrating a tolerance range of expected data 

performance of a plus or minus 25% of a 95% confidence interval of the stated standard 

requirement. NIOSH/NPPTL P&A tolerance can be higher but not lower. 

4.4. Compressed gas cylinders must meet all applicable Department of Transportation 

requirements for cylinder approval as well as retesting / requalification. 

4.5. Normal laboratory safety practices must be observed. This includes safety precautions 

described in the current NIOSH Pittsburgh Health and Safety Program. 

4.5.1. Safety glasses, lab coats, and hard-toe shoes must be worn at all times. 

4.5.2. Work benches must be maintained free of clutter and non-essential test 

equipment. 

4.5.3. When handling any broken glass laboratory equipment, lab technicians and 

personnel must wear special gloves, which protect against lacerations or 

punctures. 

4.6. Please refer to Material Safety Data Sheets and the NIOSH Health and Safety 

Manual for the proper protection and care in handling, storing, and disposing of the 

chemicals and gases used in this procedure.

5. PROCEDURE

 Note: Reference Section 3 for equipment, model numbers and manufacturers. For calibration 

purposes use those described in the manufacturer's operation and maintenance manuals. 

5.1. Follow individual instruction manuals for set up and maintenance of equipment used in 

this procedure prior to beginning testing. Malfunctioning equipment must be repaired or 

replaced and properly set up and calibrated before starting all tests. 

5.2. Calibrate photoacoustic monitor for hydrogen cyanide using a certified hydrogen cyanide 

gas cylinder at a concentration of approximately 500 ppm. 

5.3. After the manufacturer's specified warm-up period, calibrate the Gas Chromatograph 

using the Kin-Tek gas generator with the hydrogen cyanide and cyanogen permeation 
Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Procedure No. TEB-APR-STP-0513-CBRN Revision: 0.1 Date: 9 February 2009 Page 4 of 10 

tube or a certified gas cylinder of hydrogen cyanide. 

5.4. Start automatic sampling mode on the gas chromatograph. Monitor and record the 

upstream and downstream concentrations. 

5.5. Set up test equipment as shown in Figure 1. The humidity reading controlled by the 

Miller Nelson system and monitored the Dew Point Hygrometer. The sample pickup for 

the hygrometer is place into the air stream via a tee after the Miller Nelson and before the 

introduction point of challenge agent. The thermocouple for the hygrometer is placed in 

the challenge gas stream immediately before the test chamber. 

5.6. Verify the following equipment is on: 

5.6.1. Miller Nelson Unit. 

5.6.2. Air and water supplies. 

5.6.3. Gas Chromatograph 

5.6.4. NIOSH Service Life Apparatus Controller software program. 

 

5.7. Establish the correct humidity and temperature using chilled mirror dew point 

hygrometer per the test standard in paragraph 6.3. 

5.8. Set the required airflow for the system. Individual cartridges will be tested by dividing 

170 Lpm by the number of air purifying elements on the system. See appendix 8.3. 

Verify the airflow from the test fixture using the appropriate dry test meter. 

5.9. Weigh and record initial weight of the test cartridge on Test Data Sheet. 

5.10. Take and record initial airflow measurements in accordance with RCT-APR-012. See 

section 84.1152 (b) Title 42, Code of Federal Regulations, Part 84 for minimum airflow 

requirements. 

5.11. Ensure that the diverter valve in the system is diverting the challenge concentration 

airflow to the discharge and not into the test chamber. 

5.12. Mount cartridge onto test fixture in testing chamber. 

5.13. Turn on the hydrogen cyanide cylinder. 

5.14. Establish the test concentration of 470 ppm  47 ppm hydrogen cyanide. 

5.15. Once the hydrogen cyanide concentration has been established, testing may begin. 

5.16. Direct challenge concentration airflow into test chamber. 

5.17. Start timer. Airflow out of the fixture is directed into the breakthrough detector. Monitor 
Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Procedure No. TEB-APR-STP-0513-CBRN Revision: 0.1 Date: 9 February 2009 Page 5 of 10 

and record the upstream and downstream temperatures of the air stream throughout 

testing. Record breakthrough values and times. 

5.18. Run test until breakthrough of 4.7 ppm hydrogen cyanide and cyanogen is observed or 

selected service life time is surpassed. Record this data on the test data sheet. 

5.19. Direct challenge concentration airflow out of the test chamber. 

5.20. Weigh and record final weight of the test cartridge on Test Data Sheet. 

5.21. Take and record final airflow measurements in accordance with RCT-APR-012. See 

section 84.1152 (b) Title 42, Code of Federal Regulations, Part 84 for minimum airflow 

requirements. 

5.22. Allow clean air to purge through the test chamber for 5 minutes. 

5.23. Repeat steps 5.7 through 5.22 for each test described in section 6.3. 

5.24. End sampling mode program in the gas chromatograph. 

5.25. When all tests are complete turn off hydrogen cyanide cylinder, clean regulator by 

purging with air, set temperature and humidity to zero and allow air to pass through the 

system for 30 minutes. 

6. PASS OR FAIL CRITERIA

6.1. The criterion for passing this test is set forth in 42 CFR Part 84, Subpart G, Section 

84.63(a)(c)(d) and Subpart I, Section 84.110(c); Volume 60, Number 110, June 8, 1995. 

 6.2. This test establishes the standard procedure for ensuring that: 

 

84.63 Test requirements; general. 

(a) Each respirator and respirator component shall when tested by the applicant and by 

the Institute, meet the applicable requirements set forth in subparts H through L of this 

part. 

(c) In addition to the minimum requirements set forth in subparts H through L of this 

part, the Institute reserves the right to require, as a further condition of approval, any 

additional requirements deemed necessary to establish the quality, effectiveness, and 

safety of any respirator used as protection against hazardous atmospheres. 

(d) Where it is determined after receipt of an application that additional requirements will 

be required for approval, the Institute will notify the applicant in writing of these 

additional requirements, and necessary examinations, inspections, or tests, stating 

generally the reasons for such requirements, examinations, inspections, or tests. 

6.3. Acid Gas (Hydrogen Cyanide) Test for Cartridges. 
Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Procedure No. TEB-APR-STP-0513-CBRN Revision: 0.1 Date: 9 February 2009 Page 6 of 10 

6.3.1. Airflow measurements of system must be taken before and after each test. 

6.3.2. Three cartridges will be tested at the determined, continuous airflow, 25  5 

percent relative humidity (RH), 25  5o C, containing 470 ppm hydrogen cyanide. 

6.3.3. Three cartridges will be tested at the determined, continuous airflow, 80  5 

percent relative humidity (RH), 25  5o C, containing 470 ppm hydrogen cyanide. 

6.3.4. Minimum service life will be 15, 30, 45, 60, 90 or 120 minutes as per 

manufacturer request. End of service life concentration is 4.7 ppm, which is the 

sum of the breakthrough products of hydrogen cyanide and cyanogen. 

7. RECORD AND TEST SHEETS

7.1. All test data will be recorded on the CBRN HYDROGEN CYANIDE SERVICE LIFE 

test data sheet. 

7.2. All videotapes and photographs of the actual test being performed, or of the tested 

equipment shall be maintained in the task file as part of the permanent record. 

7.3. All equipment failing any portion of this test will be handled as follows: 

7.3.1. If the failure occurs on a new certification application, or extension of approval 

application, send a test report to the TEB Team Leader and prepare the hardware 

for return to the manufacturer. 

7.3.2. If the failure occurs on hardware examined under an Off-the-Shelf Audit the 

hardware will be examined by a technician and the TEB Team Leader for cause. 

All equipment failing any portion of this test may be sent to the manufacturer for 

examination and then returned to NIOSH. However, the hardware tested shall be 

held at the testing laboratory until authorized for release by the Branch Chief, or 

the Branch Chief’s designee, following the standard operating procedures 

outlined in Procedure for Scheduling, and Processing Post-Certification Product 

Audits, RB-SOP-0005-00. 

8. APPENDIXES

 8.1. Bench Top Set-Up 

 8.2. Data Sheet 

 8.3. Airflow calculations 
Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Procedure No. TEB-APR-STP-0513-CBRN Revision: 0.1 Date: 9 February 2009 Page 7 of 10 

8.1. Bench Top Set-Up 
Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Procedure No. TEB-APR-STP-0513-CBRN Revision: 0.1 Date: 9 February 2009 Page 8 of 10 

8.2. Data Sheet 
Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Procedure No. TEB-APR-STP-0513-CBRN Revision: 0.1 Date: 9 February 2009 Page 9 of 10 

8.3. Service life testing airflow calculations

Loose-fitting PAPR 

___________ Number of filtering elements on a loose-fitting PAPR System. 

170 Lpm airflow 

Airflow for service life test = 170 Lpm / number of filtering elements 

Test Flow 

4 Cartridges 3 Cartridges 2 Cartridges 1 Cartridge 

42.5 Lpm 56.7 Lpm 85 Lpm 170 Lpm 
Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Uncontrolled Copy 

 Uncontrolled Copy 

Procedure No. TEB-APR-STP-0513-CBRN Revision: 0.1 Date: 9 February 2009 Page 10 of 10 

Revision History 

Revision Date Reason for Revision 

0.0 21 November 2006 Original Issue 

0.1 9 February 2009 Name changed in alignment with current naming convention, minor 

editorial revision, no change to procedure