Approvals: 1st Level 2nd Level 3rd Level 

National Institute for Occupational Safety and Health 

National Personal Protective Technology Laboratory 

P.O. Box 18070 

Pittsburgh, PA 15236 

Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005

DETERMINATION OF PHOSPHINE SERVICE LIFE TEST 

AIR-PURIFYING RESPIRATORS 

 STANDARD TESTING PROCEDURE (STP) 

1. PURPOSE 

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

phosphine service life requirements on gas mask air-purifying respirators 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, Section 84.63(a)(c)(d) and Subpart 

I, Section 84.110(c); Volume 60, Number 110, June 8, 1995. 

2. GENERAL

This STP describes the Determination of Phosphine Service Life Test, Air-Purifying Respirator 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/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. 

3.1.2. CEA Model TG-4000BA Phosphine detector or equivalent. 

 3.1.3. Tylan Flow Controller, model RO14 

 3.1.4. Tylan mass flowmeter, 5 lpm, 2 lpm or equivalent. 

 3.1.5. Certified cylinder of 1 parts per million (ppm) PH3 in Nitrogen. 

 3.1.6. Gilian Gil-Air-3 Sampling Pump, or equivalent. 

 3.1.7. Vaisala model HMI 31 humidity indicator.

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 2 of 12 

 3.1.8. Phosphine cylinder, 99% purity. 

 3.1.9. Electronic balance with accuracy of 0.001 grams (g). 

 3.1.10. Nitrogen cylinder, 99% purity. 

 3.1.11. 4-way Purge regulator for phosphine cylinder. 

3.2. Test fixture for mounting canisters. The test fixture used is specific to each manufacturer. 

Canisters are tested with their connections glued into the ground glass joint. 

3.3. The test chamber consisting of a 12" x 11.5" x 7" air tight box, made of 1⁄2" plexiglass 

with 2 hinge type locks on the door opening lined with gasket material. A 1⁄2" hole is 

located on the backside of the test chamber for the introduction of the test concentration 

and a 1.5" hole on the top for the exit of the test fixture and to detect the breakthrough 

concentration. This fixture is not commercially available. 

3.4. Resistance tester consisting of a vacuum source capable of delivering 85 Liters per 

minute (Lpm), a 6-inch slant manometer, and a 29/42 female ground glass joint. The 

resistance testers currently being used are located on the silica dust chamber. 

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 

Standards and Technology (NIST). 

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

described in the current ALOSH Facility Laboratory Safety Manual. 

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

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

equipment. 

4.2.3. When handling any glass laboratory equipment, lab technicians and personnel 

must wear special gloves which protect against lacerations or punctures. 

4.3. PHOSPHINE BENCH TEST FOR ESCAPE GAS MASK CANISTERS 

4.3.1. Resistance to air flow will be taken before and after each test, 84.126. 

 4.3.2. Three "as received" canisters (or pairs of canisters) will be tested at 64 Lpm, 

continuous air flow, 50 + 5 percent relative humidity (RH), approximately 25 

degrees Celsius (OC), and 1500 ppm phosphine. 

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 3 of 12 

 4.3.3. Two canisters or pairs of canisters will be equilibrated at room temperature by 

passing 25 percent RH air through them at 64 Lpm for 6 hours and then testing 

them at 25 percent relative humidity, approximately 25OC, and 64 Lpm 

continuous air flow containing 1500 ppm phosphine. 

 4.3.4. Two canisters or pairs of canisters will be equilibrated at room temperature by 

passing 85 percent relative humidity air through them at 64 Lpm for 6 hours and 

then testing them at 85 percent relative humidity, approximately 25o

C, and 64 

Lpm continuous air flow containing 1500 ppm phosphine. 

 4.4. PHOSPHINE BENCH TEST FOR TIGHT FITTING PAPR GAS MASK CANISTERS 

4.4.1. Resistance to air flow will be taken before and after each test, 84.126. 

 4.4.2. Three "as received" canisters (or pairs of canisters) will be tested at 115 Lpm, 

continuous air flow, 50 + 5 percent relative humidity (RH), approximately 25 

degrees Celsius (OC), and 1500 ppm phosphine. 

 4.4.3. Two canisters or pairs of canisters will be equilibrated at room temperature by 

passing 25 percent RH air through them at 115 Lpm for 6 hours and then testing 

them at 25 percent relative humidity, approximately 25OC, and 115 Lpm 

continuous air flow containing 1500 ppm phosphine. 

 4.4.4. Two canisters or pairs of canisters will be equilibrated at room temperature by 

passing 85 percent relative humidity air through them at 115 Lpm for 6 hours and 

then testing them at 85 percent relative humidity, approximately 25o

C, and 115 

Lpm continuous air flow containing 1500 ppm phosphine. 

 4.5. 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.

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 4 of 12 

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. After the manufacturer's specified warmup period, calibrate the PH3 analyzer using the 

certified gas cylinder containing the 1 ppm standard as follows: 

5.2.1. With a tee in line on the gas cylinder, insert the intake tubing from the analyzer 

into the tee. 

5.2.2. Turn on the 1.0 ppm certified phosphine cylinder. 

5.2.3. Wait till the reading stabilizes, and adjust the span control to read 1.0 ppm. 

 5.3. Set up test equipment as shown in Figure 1. In addition to the humidity reading 

controlled by the Miller Nelson system, the Vaisala HMI 31 humidity indicator sensor is 

inserted into the air stream via a tee set-up directly prior to the introduction of the gas. 

This set up is not shown on Figure 1. The humidity reading obtained at this point takes 

into account tubing length and outside hood air temperature. 

 5.4. Turn on: 

 5.4.1. Miller Nelson Unit. 

 5.4.2. Air and water supplies. 

 5.4.3. Phosphine cylinder. 

 5.4.4. Nitrogen cylinder. 

 5.5. Establish the test concentration for 1500 ppm Phosphine in 115 lpm air. 

5.6. Calculate the rate of advance required to produce a concentration of 1500 ppm phosphine 

from Table 1. Determine the challenge test concentration via a dilution factor method by 

drawing off 1 Lpm test concentration and diluting with a known volume of clean air. By 

adjusting the rotameter and noting the deflection on the calibrated analyzer, the test 

concentration can be determined. The volume of clean air required to dilute the 1 Lpm of 

challenge concentration to produce 5000 ppm is calculated as follows: 

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 5 of 12 

 5.6.1. C1V1 = C2V2 (Where C = concentration and V = volume) 

 5000 ppm x 1 Lpm = 50 ppm x V2 

 V2 = 5000 

 50 

 V2 = 100 

 Therefore: V2 - V1 = volume of clean air 

 5.7. Draw off 1 Lpm of the phosphine in air test concentration and dilute it with the calculated 

volume of clean air for the required concentration. 

 5.8. Insert the intake tubing from the analyzer into the dilution air/gas stream. Adjust the 

rotameter till the analyzer reads 50 ppm. Note the position of the rotameter float for the 

concentration being determined. 

 5.8.1. As an example: A reading of 50 ppm for the dilution of 99 Lpm/1 Lpm 

phosphine test concentration results in a factor of 100. By using the following 

formula the total Phosphine test concentration can be determined. 

 Dilution factor x 50 ppm reading = Total Phosphine test concentration. 

 5.9. Once the Phosphine concentration has been established, testing may begin. 

 5.10. Weigh the canister and record the weight. 

 5.11. Take inhalation and exhalation resistances of the canister mounted on the facepiece at 85 

Lpm. See Sections 84.122 Title 42, Code of Federal Regulations, Part 84 for breathing 

resistance requirements. 

5.12. Mount canister onto test fixture and place in testing chamber. 

 5.13. Direct challenge concentration airflow into test chamber. Start timer. Mount small piece 

of tygon tubing onto the outlet of the test fixture. Insert intake tubing of detector into a 

slit cut into the side wall of the tubing to allow the detector to sample at the flow rate of 

the detector without interference from airflow back pressure. Monitor and record 

upstream and downstream temperatures throughout testing. Record breakthrough values 

and times. 

5.14. Run test until breakthrough of 1.0 ppm is observed or minimum service life is surpassed. 

5.15. Dismount canister, weigh and record final weight, and take final inhalation and 

exhalation resistances. 

5.16. Shut off phosphine cylinder. 

5.17. Disconnect phosphine tubing from the rotameter to prevent contamination of the 

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 6 of 12 

humidity sensor. 

5.18. Allow clean air to purge through system for 10 - 15 minutes. 

5.19. Turn off air and water supply to Miller Nelson system. 

6. PASS/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. 

 84.110. Gas masks; description. 

(c) Gas masks for respiratory protection against gases and vapors other than those 

specified in paragraph (b) of this section, may be approved upon submittal of an 

application in writing for approval to the Respirator Branch listing the gas or vapor and 

suggested maximum use concentration for the specific type of gas mask. The Institute 

will consider the application and accept or reject it on the basis of effect on the wearer's 

health and safety and any field experience in use of gas masks for such exposures. If the 

application is accepted, the Institute will test such masks in accordance with the 

requirements of this subpart. 

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 7 of 12 

7. RECORDS/TEST SHEETS

7.1. All test data will be recorded on the PHOSPHINE 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 RCT 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 RCT 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 RCT Leader, or 

his designee, following the standard operating procedures outlined in Procedure 

for Scheduling, and Processing Post-Certification Product Audits, RB-SOP0005-00. 

8. ATTACHMENTS

 8.1. Bench Top Set-Up. 

8.2. Data Sheet. 

8.3. Table 1- Concentration Calculation for Syringe Pump Injection Rates. 

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 8 of 12 

Miller-Nelson

HCS 401

64.0

25.3

50.0

Phosphine Test Setup

Gas 

Analyzer

Phosphine

Cylinder

Mixing 

“T”

Nitrogen

Cylinder

Purge valve regulator 

assembly

Tylan

Tylan

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 9 of 12 

RB - RESPIRATOR CERTIFICATION TEAM 

 GAS & VAPOR RESPIRATOR TEST DATA SHEET (Ref.33-48,50,62) STP No.: [ ] 

 Task Number: TN- Gas Name: 

Manufacturer: Item Tested: 

 

RESISTANCE Maximum Allowable Resistance 

 (mm of H2O) 

 Actual Resistance 

 (mm of H2O) 

 Inhalation Exhalation Inhalation Exhalation 

 Test 

 Initial Initial 

Final Initial Final 

 Result 

 1 

 2 

 3 

 4 

 5 

 6 

 7 

 Overall Results: Pass Fail Comment: 

WEIGHTS WEIGHTS (gm) AIRFLOW (Lpm)

 AND 

 AIRFLOWS Test Rate (PAPR Only)

 Test 

Con'd 

 

Conc. 

(ppm) RH% Lpm Initial Final 

 1 

 2 

 3 

 4 

 5 

 6 

 7 

 Overall Results: Pass Fail Comment: 

DATA TABLE Temperature (oC) 

 Test 

 Test 

 Cond. 

 Final 

 Time (min) 

 Leakage 

 (ppm) 

 Dns

tream 

 Upstr

eam 

 Corrected 

 Time (min) 

 1 

 2 

 3 

 4 

 5 

 6 

 7 

 Overall Results: Pass Fail Comment: 

 Was all testing equipment in calibration throughout all testing: Yes No 

 Signature: Date: 

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 10 of 12 

RB - RESPIRATOR CERTIFICATION TEAM Page 2 

 GAS & VAPOR RESPIRATOR TEST DATA SHEET (Ref.33-48,50,62) STP No.: [ ] 

 Task Number: TN- Gas Name: 

Manufacturer: Item Tested: 

 

Additional Comments: 

Signature: Date: 

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 11 of 12 

TABLE 1 

CALCULATIONS FOR SYRINGE PUMP INJECTION RATES at 25EC and 1 atm 

For liquids: For gases:

C= (24.6 x 106

) KRp C = RK 103 

 QM Q 

 R= CQM R = CQ 

 (24.6 x 106

) Kp K103

 where: 

 R= rate of advance (mm/min) C= concentration (ppm) 

 K= syringe constant (ml/mm) p= solvent density (g/ml) 

 Q= airflow rate (lpm) M= molecular weight (g/mol) 

Sample calculation: Find the rate of advance required to produce a concentration of 

1500 ppm phosphine gas in 115 lpm of air, using a 20 ml syringe constant. 

 R= (1500 ppm) (115 lpm)

 (.301 ml/mm) 103

 R= 0.573 mm/min. 

For calculating ml/min multiply rate in mm/minutes time the syringe constanst. syringe pumps 

delivering in volumes of ml/minute, multiply rate of advance R by syringe constant. 

 ml/min.= 0.573 mm/min. x 0.301 ml/mm. 

 ml/min.= 172.5 

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Procedure No. RCT-APR-STP-0047 Revision: 1.1 Date: 24 August 2005 Page 12 of 12 

Revision History 

Revision Date Reason for Revision 

1.0 7 March 2002 Historic document 

1.1 11 July 2001 Update header and format to reflect lab move from Morgantown, WV 

No changes to method 

 

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