NIOSH Investigation of 3M 

Model 8000 Filtering Facepiece 

Respirators as Requested by the 

California Occupational Safety 

and Health Administration, 

Division of Occupational Safety 

and Health 

Roland Berry Ann

Health Hazard Evaluation Report

HETA 2010-0044-3109

California Occupational Safety and Health 

Administration, Division of Occupational 

Safety and Health 

Oakland, California

May 2010

Department of Health and Human Services

Centers for Disease Control and Prevention

Workplace

Safety and Health

 National Institute for Occupational 

Safety and Health

This Health Hazard Evaluation (HHE) report and any recommendations made herein are for the specific 

facility evaluated and may not be universally applicable. Any recommendations made are not to be 

considered as final statements of NIOSH policy or of any agency or individual involved. Additional HHE 

reports are available at http://www.cdc.gov/niosh/hhe/
This page intentionally left blank.
Health Hazard Evaluation Report 2010-0044-3109 Page i

Appendix A

Report Abbreviations.......................................................................ii

Highlights of the NIOSH Health Hazard Evaluation............ iii

Summary .............................................................................v

Introduction..........................................................................1

Assessment.........................................................................2

Results.................................................................................8

Discussion .........................................................................10

Conclusions.......................................................................11

Contents

NIOSH Standard Test Procedure No. 

TEB-APR-STP-0003..........................................................25

 3M Model 8000, N95 Filtering Facepiece Respirators......12

 

NIOSH Standard Test Procedure No. 

TEB-APR-STP-0059..........................................................13

Acknowledgments

Appendix B

Appendix C

Appendix D NIOSH Standard Test Procedure No. 

TEB-ARP-STP-0007..........................................................34

Test Sample Respiratiors Prepared for Filter Efficiency and 

Airflow Resistance (Inhalation/Exhalation) Testing............45

Appendix E

Appendix F 40-Member NIOSH Bivariate Fit Test Panel for NIOSH 

Investigation of 3M Model 8000 Filtering Facepiece 

Respirator Fit Testing.........................................................46

Acknowledgments and Availability of Report.....................47
Page ii Health Hazard Evaluation Report 2010-0044-3109

Cal/OSHA California Occupational Safety and Health Administration, 

Division of Occupational Safety and Health

CDC Centers for Disease Control and Prevention

CDPH California Department of Public Health

CFM Cubic feet per minute

CFR Code of Federal Regulations

FFR Filtering facepiece respirator

HETA Hazard Evaluations and Technical Assistance

Lpm liters per minute

mg/m3 milligrams per cubic meter

NAICS North American Industry Classification System

NIOSH National Institute for Occupational Safety and Health

NPPTL National Personal Protective Technology Laboratory

OSHA Occupational Safety and Health Administration

PPT Personal protective technology

SME Subject matter expert

STP Standard test procedure

Abbreviations
Health Hazard Evaluation Report 2010-0044-3109 Page iii

Highlights of the

NIOSH Health

Hazard Evaluation

On December 23, 2009, 

the National Institute for 

Occupational Safety and 

Health (NIOSH) received 

a technical assistance 

request from the 

California Occupational 

Safety and Health 

Administration, Division 

of Occupational Safety 

and Health. The request 

reported a concern over 

difficulties fitting 3M 

Model 8000 respirators 

among employees 

exposed to 2009 H1N1 

pandemic influenza at 

several facilities of a large 

healthcare organization. 

The organization had 

received the respirators in 

a distribution of product 

from the California 

Department of Public 

Health (CDPH) respirator 

stockpile. 

What NIOSH Did 

● The performance of sample 3M Model 8000 filtering 

facepiece respirators (FFRs) received from the CDPH 

stockpile were checked to confirm their ability to meet the 

same requirements as needed for NIOSH approval. A series 

of evaluations and document reviews were performed by 

NIOSH subject matter experts.

● Performance tests were conducted to determine filter 

efficiency.

o Airflow resistance performance tests were 

conducted to ensure the breathing resistance did 

not exceed the maximum pressure drop allowed for 

NIOSH approval.

o Visual inspections were conducted with sample 

respirators for evidence that they were wellconstructed of good materials and workmanship 

(e.g. placement, attachment, length, elasticity of 

headband straps).

o Detailed document reviews were performed of 

NIOSH and 3M quality assurance documentation 

to ensure there weren’t any issues or concerns 

of non-compliance with normal quality control 

practices or requirements of the 3M quality control 

plan during the manufacture of the respirators 

stockpiled by the CDPH.

● A literature search was conducted to review all peerreviewed, published respirator research studies that specified 

the 3M Model 8000 respirator as a model whose fitting 

characteristics were assessed. 

● Unpublished laboratory test results were reviewed to assess 

data on fit test trials following FFR decontamination 

procedures on FFR models of similar construction to the 3M 

model 8000 respirator. 

● Twenty 3M Model 8000 N95 FFRs were tested to validate 

conformity with NIOSH certification procedures.

● Sample 3M Model 8000 FFRs for 2 sets of tests, were 

evaluated for their performance on a panel of 40 human 

test subjects representing a variety of facial features 

proportionately distributed across the NIOSH bivariate 

panel. 
Page iv Health Hazard Evaluation Report 2010-0044-3109

Highlights of the

NIOSH Health

Hazard Evaluation

(continued)

What NIOSH Found

● The performance tests and review of quality assurance 

records and inspections for quality of materials and 

workmanship revealed compliance with applicable 

approval requirements. The 3M Model 8000 respirators 

representatives of the CDPH stockpile: 

o Met the filter efficiency requirements for the 

approval of N95 FFRs.

o Met the airflow resistance requirements for the 

approval of N95 FFRs.

o Did not exhibit any issues or cause concerns of noncompliance with normal quality control practices or 

the requirements of the 3M quality control plan. 

● No peer-reviewed published research studies were identified 

that specified the 3M Model 8000 respirator as one of the 

tested respirator models. 

● In reviewed unpublished laboratory test results, subject 

matter experts found a pass rate of approximately 40% to 

60% of test subjects to be within the expected performance 

levels for FFRs of similar construction to the 3M Model 8000 

respirator.

● The sample respirators demonstrated fit test passing results 

on 22 and 25 of the 40 subjects in the two sets of trials.
Health Hazard Evaluation Report 2010-0044-3109 Page v

Summary

NIOSH investigators 

assessed sample units 

of the 3M Model 8000 

FFRs received from the 

CDPH stockpile in order 

to check for any noncompliance with the NIOSH 

approval requirements 

for filtration efficiency 

and airflow (breathing) 

resistance. The goal was to 

determine if the respirators 

were manufactured in 

accordance with the 

NIOSH-approved quality 

assurance plan and had 

appropriate construction 

and workmanship. The 

investigation also evaluated 

respirator performance 

when fit tested on a panel 

of human test subjects 

representing a variety of 

facial dimensions. The 

evaluation revealed that 

the performance tests, 

reviews of quality assurance 

records, and material and 

workmanship inspections 

were in compliance with 

applicable approval 

requirements. Additionally, 

sample respirators had fit 

test passing results on 22 

and 25 of the 40 subjects 

in two trials. The NIOSH 

investigation determined 

that the fit test pass rate 

reported at the various 

facilities of a California 

healthcare organization did 

not result from any defect 

in the units’ characteristics 

on which the product was 

certified.

The CDPH established a stockpile of respirators for use by 

healthcare personnel during an outbreak of pandemic influenza. 

The stockpile included an assortment of FFRs including 

approximately 32 million 3M Model 8000 N95. The CDPH’s 

stockpile of respirators was made available for healthcare worker 

use during an outbreak of pandemic influenza in Fall, 2009. 

In addition to the CDPH’s reserves, the CDC distributed a 

supplement of approximately 4 million 3M Model 8000 N95 FFRs 

to the CDPH from the federal government’s Strategic National 

Stockpile, which is maintained and managed by CDC. Healthcare 

facilities within California that were experiencing shortages of 

respirators for the protection of healthcare personnel received 

respirators distributed from the CDPH stockpiled respirators, 

including this 3M model. 

On December 23, 2009, NIOSH received a request for assistance 

from Cal/OSHA. Cal/OSHA was concerned that a large 

healthcare organization was unable to successfully fit test their 

healthcare workers with the 3M Model 8000 N95 FFR received 

from the California stockpile. The healthcare organization 

conducted the initial set of fit tests using the Bitrex® qualitative fit 

test protocol, and none of the approximately 20 workers who were 

fit tested obtained an acceptable fit (pass rate of 0%). A second 

group of 20 workers were reported to have obtained a fit test pass 

rate of 40% (8 of 20) with fit tests conducted by 3M representatives 

using the TSI PortaCount® with N95 Companion® quantitative 

fit test protocol. The California experience with these devices 

raised questions about whether the subject units had a defect of 

some type whereby they may have been non-conforming to the 

NIOSH approval. SMEs from the NIOSH NPPTL conducted the 

technical assistance investigation. 

The purpose of the NIOSH investigation was to determine 

whether the fit test pass rate reported at the various facilities of 

a California healthcare organization resulted from any defect in 

the units’ characteristics on which the product was certified (e.g., 

filter efficiency at the N95 criteria, workmanship, or quality of 

manufacture) as believed by Cal/OSHA and CDPH. To address 

the concerns, NIOSH requested and received samples from the 

remaining stockpiled 3M Model 8000 respirators from CDPH 

for inspection, testing and evaluation. The activities were divided 

into five parts: (1) assessment of compliance with requirements 

for NIOSH respirator certification, (2) assessment of conformance 

with quality assurance provisions incorporated into the NIOSH 
Page vi Health Hazard Evaluation Report 2010-0044-3109

Summary (continued)

approval, (3) respirator research review, and (4) fit test trials using 

the CDPH-supplied 3M 8000 respirators.

This investigation was limited to conformity assessment of the 

respirators to the NIOSH approval requirements and did not 

include efforts to evaluate the California healthcare organization’s 

fit testing programs, or to conduct additional fit testing on the 

actual healthcare workers who failed the California fit tests. 

The investigation revealed that the 3M Model 8000 respirators 

complied with all applicable approval requirements, which do 

not include assessment of fit characteristics. The respirators were 

additionally tested for their ability to fit test subjects representative 

of the NIOSH Bivariate fit test panel. The sample respirators 

demonstrated fit test passing results on 22 and 25 of the 40 

subjects in the two sets of trials. 

The investigation found no issues or concerns of non-compliance 

with normal quality control practices or the requirements of 

the 3M quality control plan during the manufacturing of the 

respirators in the CDPH stockpile. As a result of these findings, 

no further actions will be taken. 

Keywords: NAICS 622110 (General Medical and Surgical 

Hospitals), Healthcare, Cal/OSHA, filtering facepiece respirator, 

filtration efficiency, breathing resistance, respirator performance.
Health Hazard Evaluation Report 2010-0044-3109 Page 1

Introduction

Cal/OSHA was notified in November 2009, by a large healthcare 

organization of difficulties in fitting the distributed 3M Model 

8000 respirators to workers at several of their facilities. Based upon 

recent fit testing at hospitals in California, 3M Model 8000 N95 

FFRs from the CDPH Stockpile achieved fit test pass rates that were 

deemed to be unacceptably low for use by the healthcare workers. 

This experience caused CDPH and Cal/OSHA to believe the model 

8000 respirators distributed from the California stockpile to be 

unusable due to defects in those units. The Cal/OSHA Division of 

Occupational Safety and Health contacted NIOSH on December 

23, 2009 to request NIOSH’s assistance. Cal/OSHA reported to 

NIOSH that the healthcare organization conducted the initial set 

of fit tests using the Bitrex® qualitative fit test protocol and none 

of the approximately 20 workers who were fit tested obtained an 

acceptable fit (pass rate of 0%). A second group of 20 workers were 

reported to have obtained a fit test pass rate of 40% (8 of 20) with fit 

tests conducted by 3M representatives using the TSI PortaCount® 

with N95 Companion® quantitative fit test protocol. Cal/OSHA 

also notified its stakeholders of this issue on December 23, 2009. 

The California experience with these devices raised questions 

about whether the subject units had a defect of some type whereby 

they may have been non-conforming to the NIOSH approval. A 

widespread quality problem would have immediate implications for 

other respirator purchasers who have stockpiled this particular model 

of respirator. The NIOSH NPPTL initiated a technical assistance 

investigation of the stockpiled 3M Model 8000 N95s under the 

health hazard evaluation program based on the Cal/OSHA request 

for assistance. 

Background

The 3M Model 8000 N95 FFR is approved by NIOSH and, 

as a condition of approval, must be used in the context of a 

comprehensive respiratory protection program. When respirators 

are used in the workplace regulated by OSHA, a comprehensive 

respiratory protection program must be in place as required by 

OSHA’s Respiratory Protection standard 29 CFR 1910.134. This 

investigation did not include efforts to evaluate the California 

healthcare organization’s fit testing programs, or to conduct 

additional fit testing on the actual healthcare workers who failed 

the California fit tests. The purpose of this investigation was to 

determine whether the fit test pass rate reported at the various 

facilities of a California healthcare organization resulted from any 

defect in the units’ characteristics on which the product was certified 

(e.g., filter efficiency at the N95 criteria, workmanship, or quality 

of manufacture). To address these concerns, NIOSH requested and 

received samples from the remaining stockpiled 3M Model 8000 

respirators from CDPH for inspection, testing, and evaluation. 

The sample respirators that NIOSH received for this investigation 

were labeled as being manufactured during either of two production 
Page 2 Health Hazard Evaluation Report 2010-0044-3109

Introduction 

(continued)

Assessment

lots: lot 17040-05 or lot 17040-06. The investigation was conducted to 

assess the sample units of the 3M Model 8000 FFRs received from the 

CDPH stockpile for any non-compliance with the NIOSH approval 

requirements for performance of filtration efficiency and airflow 

(breathing) resistance. The goal was to determine if the respirators 

were manufactured in accordance with the NIOSH-approved quality 

assurance plan, and that the respirators showed no evidence of 

poor workmanship. The investigation also evaluated respirator 

performance when fit tested on a panel of human test subjects 

representing a variety of facial dimensions. The activities were divided 

into five parts: (1) assessment of compliance with requirements for 

NIOSH respirator certification, (2) assessment of conformance with 

quality assurance provisions incorporated into the NIOSH approval, 

(3) respirator research review, and (4) fit test trials using the CDPHSupplied 3M 8000 respirators.

Appendix A provides photographs showing the 3M Model 8000 FFR 

(obtained from advertising sources). Figure A1 shows the 3M Model 

8000 respirator, with the NIOSH abbreviated approval label. Figure 

A2 includes the normal 3M packaging.

Assessment of Compliance with 

Requirements for NIOSH Respirator 

Certification 

 Approval requirements with the potential to affect the 

 respirators’ ability to fit properly were identified as:

● Filter efficiency and airflow resistance tests, and

● Visual assessment for quality of materials and workmanship 

evidenced in the sample units.

Filter efficiency and airflow resistance tests

NIOSH conducted performance tests used in the respirator 

certification program on sample respirators from both manufacturing 

production lots (lot 17040-05 and lot 17040-06). Ten respirators 

from each lot received from the CDPH stockpile were used for the 

filter efficiency testing. The filter efficiency tests were conducted 

on the 20 respirators in accordance with the National Institute for 

Occupational Safety and Health (NIOSH) Standard Test Procedure No. 

TEB-APR-STP-0059, Determination of Particulate Filter Efficiency Level for 

N95 Series Filters Against Solid Particulates for Non-Powered, Air-Purifying 

Respirators (Appendix B). This test procedure ensures that the level of 

protection of N95 series filters used on non-powered respirators meet 

the minimum certification standards set forth in 42 CFR part 84, 
Health Hazard Evaluation Report 2010-0044-3109 Page 3

Assessment (continued) Subpart G, Section 84.181. The airflow resistance tests on the sample 

respirators were conducted in accordance with the National Institute 

for Occupational Safety and Health (NIOSH) Standard Test Procedure No. 

TEB-APR-STP-0003, Determination of Exhalation Resistance Test, AirPurifying Respirators (Appendix C), and National Institute for Occupational 

Safety and Health (NIOSH) Standard Test Procedure No. TEB-APR-STP0007, Determination of Inhalation Resistance Test, Air-Purifying Respirators 

(Appendix D) to ensure the FFRs met the minimum certification 

standards for airflow resistance requirements set forth in 42 CFR 

part 84, Subpart G, Section 84.180 for filters used on non-powered 

respirators. 

The FFRs were pre-conditioned at 85 +/- 5% relative humidity and 

38 +/-2.5oC for 25 +/- 1 hours. Each FFR was mounted and sealed 

on holders to prevent leakage around the filter holder and tested 

at a challenge flow rate of 85 +/- 4 Lpm using a TSI Model 8130 

Automated Filter Tester (TSI Incorporated, Shoreview, Minnesota). 

The filters were challenged with a sodium chloride aerosol at 25 +/- 5

o

C and a relative humidity of 30 +/- 10% that had been neutralized 

to the Boltzmann equilibrium state. The challenge aerosol had a 

particle size distribution of a count median diameter of 0.075 +/- 

0.020 micrometer and a geometric standard deviation not exceeding 

1.86. Each FFR was challenged with an aerosol concentration not 

exceeding 200 mg/m3 in accordance with the test procedure. Tests 

were conducted, and the results recorded in accordance with the 

appropriate STPs. Appendix E contains photographs of the sample 

respirators as they were prepared for the filter efficiency and airflow 

resistance performance tests. Figures E1 and E2 show the respirators 

with the headband straps removed to allow mounting and sealing 

on the filter holder to prevent airflow leakage around the edge of 

the filter as mounted for testing. Figures E3 and E4 show sample 

respirators after mounting and sealing with beeswax to the flat 

Plexiglas plate used for most FFRs in this filter testing. 

Visual assessment for quality of materials and 

workmanship

The sample respirators were also inspected for visual evidence of good 

materials and workmanship. Similar visual assessments have been 

part of the normal certification evaluation activities to make sure that 

the units submitted for approval evaluation are well-constructed (e.g. 

placement, attachment, length, and elasticity of headband straps).

Assessment of Conformance with Quality 

Assurance Provisions Incorporated into 

the NIOSH Approval

NIOSH evaluates proposed quality control processes and procedures 

to monitor the manufacturing of certified respirators in order to 
Page 4 Health Hazard Evaluation Report 2010-0044-3109

Assessment (continued) assure their continued quality during documentation review of 

approval applications. NIOSH also conducts post-certification 

auditing of manufacturing sites and off-the-shelf certified products 

for compliance to the quality assurance related requirements of the 

products’ approval. For this investigation, NIOSH reviewed the 

NIOSH-accepted quality control documentation for the certification 

of the 3M Model 8000 respirator and the post-certification auditing 

of the manufacturing site. NIOSH also reviewed the 3M quality 

control records from the monitoring of both manufacturing 

production lots, lots 17040-05 and 17040-06, in which the sample 

respirators were produced. 

Quality assurance requirements for the 3M Model 

8000 respirator

The 3M Model 8000 respirator is manufactured in a two step process. 

The cup part is molded in the first step. The straps and noseclip 

are affixed to the molded cup in the second, finishing step. The 3M 

Quality Control plan which is incorporated as part of the NIOSHcertification documentation includes two types of testing and 

procedures to be conducted for the manufacturing process. In-process 

testing of sodium chloride initial filter penetration and breathing 

resistance is done on samples of each manufacturing lot of the 

molded cup before they enter into the finishing step. Sample finished 

products are checked for sodium chloride initial filter penetration 

at the conclusion of the finishing step. An additional sample for 

each manufacturing production lot of the molded cup is tested to 

200 milligram loading of the sodium chloride aerosol, as part of the 

release testing in accordance with the quality control plan. 

Review of NIOSH quality assurance 

documentation 

The two manufacturing production lots represented by the sample 

3M Model 8000 FFRs received from the CDPH stockpile, lot 

17040-05 and lot 17040-06, were identified as manufactured at the 

3M Aberdeen, South Dakota facility. A review was conducted of 

the NIOSH documentation of recent manufacturing site quality 

assurance audits of that facility. A manufacturing site audit was 

completed on November 22, 2005, and another was conducted on 

October 30, 2008. 

Review of 3M quality assurance documentation

Molded cups used at the finishing step of a single production lot 

can include cups molded in multiple lots from the molding step. 
Health Hazard Evaluation Report 2010-0044-3109 Page 5

Assessment (continued) Therefore, the assembled respirators identified as produced within 

a single finishing step production lot can include molded cups from 

either the same day or several days of the molding step production. 

Molded cups from lots 17040-05 and 17040-06 were used in three 

finishing step (final) lots. The 3M quality control documentation 

from the in-process and final release testing of all molding step 

and finishing step lots that would be contained in manufacturing 

production lots 17040-05 and 17040-06 were obtained from 3M. 

NIOSH reviewed the 3M quality records as part of the investigation’s 

quality assurance assessment. 

Respirator Research Review

NIOSH conducts PPT research to advance the state of science and 

close knowledge gaps concerning personal protective equipment and 

its use. The NIOSH research is conducted in support of, and as part 

of the NIOSH PPT Program. 

Literature review of published research studies

NIOSH researchers conducted a literature search and review of peerreviewed published respirator research studies that assessed respirator 

fitting characteristics. The NIOSH-conducted literature review of 

available research reports did not identify any peer-reviewed published 

research studies that specified the 3M Model 8000 respirator as one 

of the tested respirator models in a reported study.

Review of unpublished NIOSH data 

The NIOSH researchers were aware of unpublished data collected 

during a NIOSH research project evaluating the ability of FFRs to be 

decontaminated after exposure to bioaerosols. The 3M Model 8000 

respirator was one of the six FFR models included in the NIOSH 

study because it was one of the FFR models in the CDC Strategic 

National Stockpile. The determination of the fitting performance of 

the six FFR models used was not a goal of the study. However, the 

impact of subjecting the various respirator models to the candidate 

decontamination procedures on the FFR fitting characteristics was 

unknown. The NIOSH researchers anticipated that the study might 

be expanded to include fit assessments on human test subjects 

before and after potential decontamination procedures. They 

conducted fit test trials using a number of human test subjects with 

samples of the respirator model prior to their being subjected to 

the decontamination techniques. This process was done for the 

various models so baseline performance data would be available to 

evaluate the ability of FFRs to retain their fitting characteristics after 

undergoing decontamination procedures. 
Page 6 Health Hazard Evaluation Report 2010-0044-3109

Assessment (continued) For the decontamination study, 18 human test subjects who typically 

are among the available test subjects for NIOSH respirator test 

procedures were available for fit test trials, and were fit tested on the 

3M Model 8000 FFRs before the respirators were subjected to the 

biological decontamination methods. The 18 test subjects did not 

represent the full range of facial dimensions reflected in either the 

Los Alamos National Laboratory panel developed for NIOSH in the 

1970’s or the recently-developed NIOSH Bivariate panel. The NIOSH 

Bivariate panel, based on a 2003 NIOSH-conducted anthropometric 

survey of 3,997 US workers, represents the diverse range of facial 

dimensions of respirator wearers in the US workforce. Fit test trials 

using the TSI PortaCount® with N95 Companion® were conducted 

on the 18 available test subjects. 

Fit Test Trials with the CDPH-Supplied 3M 

8000 Respirators

The NIOSH respirator certification program is supported through 

the development and promulgation of standards and regulations. 

NIOSH conducts applied research and develops test procedures in 

support of the activities to develop criteria for evaluation of proposed 

performance parameters for PPT. NIOSH conducted two sets of 

performance tests to assess the fitting capability performance of 

the sample respirators from the CDPH stockpile. One set of tests 

were conducted using a 40-member NIOSH Bivariate panel and 

representative samples for each of the two manufacturing production 

lots. 

Background for NIOSH fit test trials 

The two separate lots of 3M Model 8000 FFRs (17040-05 and 17040-

06) were quantitatively fit tested on a panel of 40 human test subjects 

at the NIOSH test facilities, Pittsburgh, Pennsylvania. The human test 

subjects were experienced respirator wearers from within the group 

of persons normally used for test panel evaluations of respirator fit 

in the NIOSH respirator certification program. Participating human 

test subjects for these fit test trials were selected based on their facial 

dimensions meeting the proportional distribution of facial sizes of 

the NIOSH Bivariate panel, and their availability for completing 

the six fit test trials being conducted for this investigation (3 trials 

using a respirator from each production lot was performed for both 

production lots representative of the CDPH stockpile of respirators). 

The facial dimensions of the 40 human subjects used for this test 

program were proportionally distributed into the NIOSH Bivariate 

panel (see Appendix F).
Health Hazard Evaluation Report 2010-0044-3109 Page 7

Assessment (continued) Conduct of the NIOSH fit test trials

The fit test trials were conducted by NIOSH personnel using the 

TSI PortaCount® with N95 Companion®. The OSHA-accepted 

fit test protocol and exercise regimen were followed. As with the 

OSHA-accepted fit test protocol, an overall fit factor equal to or 

greater than 100 was used for the pass/fail fit factor for all fit test 

trials. TSI, Inc. FitPlus version 3 Fit Test software was used to 

administer all fit test trials. This software provides a fully automated 

fit test process that includes and follows the OSHA Fit Test Protocol 

exercise routines and sequence. After entering the start command, 

the first exercise description appears as a graphic progress bar. As each 

exercise completes, the FitPlus version 3 Fit Test software provides 

a warning to indicate that it is time to begin the next exercise and 

continues this process until all exercises are completed. Additionally, 

test subjects were instructed to take only one breath at each exercise 

hold point, where applicable (head side-to-side, head up-and-down, 

etc.) in a further attempt to minimize variability in performing the 

exercise regimen among the trials. Each respirator was probed prior 

to the start of testing, with the PortaCount sample line connected to 

the mask probe before the test subject donned the respirator. The 

PortaCount sampling pendant was installed after the respirator was 

donned. The pendant was used to hold the sample line in place on 

the test subject’s chest, thereby minimizing the sampling line pulling 

on the FFR during the fit test exercises. 

Each fit test trial required a donning conducted in strict accordance 

with 3M’s instructions and the test subject’s independent assessment 

that the user’s seal check successfully represented an acceptable fit 

had been attained. Prior to testing, each test subject reviewed the 

3M user instructions to familiarize themselves with the selection, 

donning, and fitting procedures for the 3M Model 8000 respirator. 

Each test subject performed an assisted donning of the pre-probed 

respirator in accordance with the manufacturer’s user instructions 

and was permitted to make the appropriate adjustments until satisfied 

they were wearing the respirator in accordance with the instructions. 

Test administrators monitored the donnings to assure that the FFR 

was properly donned by the test subject and provided additional 

training as necessary to assure conformance to the user instructions 

during respirator donning and adjustment. Following a user seal 

check and documentation of the results, each test subject wore the 

respirator for at least 5 minutes before beginning the test. After 

completion of each fit test trial, the respirator was doffed and the 

metal noseclip was reshaped to its original configuration by the test 

operator prior to the respirator being re-donned for the next fit test 

trial. This was done to assure that the same fitting procedures were 

required to be performed every time the respirator was donned in a 

fit test trial. 
Page 8 Health Hazard Evaluation Report 2010-0044-3109

Assessment (continued) Each of the 40 test subjects performed a total of six fit test trials 

consisting of three donnings of a respirator for each production lot 

(17040-05 and 17040-06) received from the CDPH stockpile. One 

respirator was used for the set of three trials for each production lot. 

For this investigation, a test subject receiving at least one acceptable 

fit test result, i.e., a fit factor of 100 or greater, from the three trials 

per respirator was defined as having passed the fit test with that 

respirator. 

 

No issues of non-conformance to the approval requirements for this 

respirator model were identified in any of the assessments performed 

under this investigation. No acceptable minimum pass rate was 

established for fit test trials of the 3M Model 8000 respirators. The 

sample respirators demonstrated fit test passing results on 22 (55%) 

and 25 (62.5%) of the 40 subjects in the two sets of trials. 

Summary of Results for NIOSH Activities 

Assessing Compliance with Certification 

Requirements

No issues of non-compliance were identified in the assessment of 

approved performance, materials, and workmanship. All NIOSH 

certification requirements assessed by the performance testing 

and visual inspections conducted by NIOSH personnel on the 20 

sample respirators were judged to be met. Based on these results, 

the respirators produced in lot 17040-05 and lot 17040-06 were 

determined to have been manufactured in conformance with the 

terms of the NIOSH certification of the 3M Model 8000 FFR. 

Summary of Results for Activities 

Assessing Compliance with Quality 

Assurance Requirements

Only three minor findings, identified as a consequence of the 

October 2008 audit, were noted from auditing of the Aberdeen 

manufacturing facility. The minor findings from this audit have 

since been resolved. The detailed review of NIOSH and 3M quality 

assurance documentation for the manufacture of the 3M Model 

8000 FFR did not reveal any issues or concerns of non-compliance 

with normal quality control practices or the requirements of the 

3M quality control plan incorporated as a condition of NIOSH 

certification. 

Results
Health Hazard Evaluation Report 2010-0044-3109 Page 9

Results (continued) Summary of Results for NIOSH Activities 

Assessing Literature Review of Research 

Studies

The NIOSH researchers reviewed the unpublished data for fit test 

trials performed during a NIOSH project investigating FFRs subjected 

to potential decontamination procedures. Twelve of 18 test subjects 

were able to achieve acceptable results of a protection factor of 100 or 

more using the 3M Model 8000 respirators. The facial dimensions of 

most of these test subjects placed them in the middle of the NIOSH 

Bivariate panel, and, therefore, their face size distribution was not 

representative of the U.S. population. Although the results do not 

represent actual workplace conditions, they do serve as an indicator 

of performance likely representing a scenario that can be used as a 

guide for potential fit test performance of this respirator model. No 

acceptable minimum pass rate has been established for fit test trials 

of FFRs. The data from fit test trials of the various FFR models in the 

NIOSH decontamination study included results of higher pass rates 

for some models and lower pass rates for others. As a result of this 

review, the experience and professional judgment of NIOSH research 

SMEs found a pass rate of approximately 40% to 60% of test subjects 

to be within the expected performance levels for FFRs of similar 

construction to the 3M Model 8000 respirator for comparison with 

the reported California experience and the fit test trials conducted by 

NIOSH in this investigation. Unpublished data within the NIOSH 

project database were consistent with these expectations.

Summary of Results for Activities 

Assessing Fitting Characteristics

No acceptable minimum pass rate was established for the fit test trials 

of the 3M Model 8000 respirators. Using the investigation criteria 

for conducting the fit test trials and determining whether the fit test 

had been passed by a test subject, the following fit test pass rates were 

achieved by the 40 panel members:

22 test subjects of the 40-member panel (55%) achieved passing 

results on the NIOSH -conducted fit tests using the OSHAaccepted TSI PortaCount® with N95 Companion® fit test 

protocol and respirators from lot 17040-05. 

25 test subjects of the 40-member panel (62.5%) achieved 

passing results on the NIOSH -conducted fit tests using the 

OSHA-accepted TSI PortaCount® with N95 Companion® fit 

test protocol and respirators from lot 17040-06.
Page 10 Health Hazard Evaluation Report 2010-0044-3109

NIOSH technical assistance investigation of the 3M Model 8000 

N95 FFR was initiated by the NIOSH NPPTL based on the Cal/

OSHA notification of a suspected product defect and request for 

assistance. The investigation included NIOSH evaluation, inspection, 

and testing of fit-related parameters of representative samples of the 

California-stockpiled respirators of this model. The filter efficiency 

and airflow (breathing) resistances of the tested respirators met 

the performance requirements for NIOSH FFR approval. The 

NIOSH-conducted investigation did not reveal any issues where 

the representative respirators exhibited non-compliance with the 

approval requirements. Fit test trials resulted in 40 test subjects 

with facial dimension sizes and distribution in accordance with the 

NIOSH bivariate panel achieving fit test passing results for 22 (55%) 

of 40 subjects in one set of trials and 25 (62.5%) of 40 subjects in 

the second set of trials. No acceptable minimum pass rate has been 

established for fit test trials of FFRs.

The reported pass rate of 0% for the Bitrex® qualitative fit tests 

conducted by the healthcare organization for the initial set of 

approximately 20 workers, as well as the pass rate of 40% (8 of 

20) for a second group of 20 workers who were fit tested by 3M 

representatives using the TSI PortaCount® with N95 Companion® 

quantitative fit test protocol, are neither inconsistent with each 

other, nor with the results of the fit test trials conducted under 

this investigation. The consequences of momentary or shortterm breaches in the seal between the respirator’s sealing surface 

and the test subject’s face can be significantly different between a 

qualitative fit test and a quantitative fit test. The pass/fail criteria 

for a qualitative fit test protocol relies on the test subject’s sensory 

detection of the test agent at any time during the conduct of the test, 

while the determination for quantitative fit test protocols is based on 

the overall protection level determined by averaging the protection 

levels measured for the individual exercises used in the protocol. 

The Bitrex® qualitative fit test protocol depends on the worker’s 

detection of the bitter taste of the Bitrex at the sensitivity level to 

determine a protection level less than the acceptable minimum. 

A momentary breach in the seal between the respirator’s sealing 

surface and the test subject’s face during any portion of the protocol’s 

exercise regimen may be detected, thereby causing failure of the fit 

test. A similar momentary breach in the seal during a quantitative 

fit test may be evidenced in a much lower protection level reading 

for the time period that the breach exists, but not reduce the overall 

protection factor enough to result in a failure of the fit test. How 

many of the workers who failed the Bitrex® fit test protocol due 

to short-term breaches in the respirator-to-user seal would have 

passed a quantitative fit test for that same donning is unknown. 

However, the respirators’ performances were consistent with NIOSH 

experience and professional judgment of expected performance 

based on respirator research, certification, and policy and standards 

development activities.

Discussion
Health Hazard Evaluation Report 2010-0044-3109 Page 11

Discussion (continued) The 3M Model 8000 FFR is designed as a single-sized design. The 

California experience underscores the longstanding OSHA and 

NIOSH positions on the importance of fit testing to assure that the 

particular make and model of respirator selected actually fits each 

individual worker who will use it. No respirator can be guaranteed to 

fit 100% of users, and OSHA regulations require an assortment of 

models and sizes of respirators be available for selection at the time 

of fit testing. Due to anthropometric differences in the American 

workforce, a variety of respirators may have to be tested to achieve a 

good fit for an individual worker. The experience also highlights the 

importance of and need to assure that multiple makes/models/sizes 

of respirators are acquired to provide users with a variety of respirator 

fit options. 

The 40% fit test pass rate reported by Cal/OSHA for the 3M Model 

8000 FFR as part of the request for NIOSH assistance does not 

indicate that the units of this model are defective. No acceptable 

minimum pass rate has been established for workplace fit testing 

of a respirator model. Numerous factors aside from defects to 

the respirator units can affect the fit test outcome, such as worker 

facial dimensions, the ability and ease of conforming the respirator 

seal (including the noseclip) to the worker’s face, the quality of the 

administration of the fit test protocol, type and level of training 

provided to intended users, the experience levels and expectations 

of the workers being fit tested, etc. The fit test trials conducted 

under this NIOSH investigation were performed on a representative 

panel of 40 experienced test subjects with facial size distributions 

that approximate the facial sizes and distributions representative of 

respirator users in the U.S. workforce.

The purpose of this investigation was to determine if there was a 

widespread quality problem that caused the subject units to have 

a defect of some type whereby they may be non-conforming to the 

NIOSH approval. Therefore, this investigation did not include 

efforts to evaluate the California healthcare organization’s fit testing 

programs, or to conduct additional fit testing on the actual healthcare 

workers who failed the California fit tests. The facial dimensions of 

the approximately 40 workers who participated in the fit testing at 

the California facilities and their distribution within the respirator 

user population is undetermined. At this time there is no evidence of 

a defect in the respirators or any indication that the respirators will 

not achieve the expected level of protection when used in accordance 

with the respirator standard (e.g., successful fit test, training, etc.). 

Conclusions
Page 12 Health Hazard Evaluation Report 2010-0044-3109

 3 Appendix A: M Model 8000, N95 Filtering Facepiece

Respirators

Figure A1. 3M Model 8000 respirator with the NIOSH abbreviated approval label.

Figure A2. 3M Model 8000 respirator with normal packaging.
Health Hazard Evaluation Report 2010-0044-3109 Page 13

Appendix B, C, D: 

Appendix B: NISOH Standard Test Procedure No. TEB-APR-STP0059 is on the web at:

http://www.cdc.gov/niosh/npptl/stps/pdfs/TEB-APR-STP-0059.pdf

Appendix C: NISOH Standard Test Procedure No. TEB-APR-STP0003 is on the web at:

http://www.cdc.gov/niosh/npptl/stps/pdfs/RCT-APR-0003.pdf

Appendix D: NISOH Standard Test Procedure No. TEB-APR-STP0007 is on the web at:

http://www.cdc.gov/niosh/npptl/stps/pdfs/TEB-APR-STP-0007.pdf
Page 14 Health Hazard Evaluation Report 2010-0044-3109

 Test Sample Respiratiors Prepared for Filter Efficiency

and Airflow Resistance (Inhalation/Exhalation) Testing

Appendix E:

Figure E1. Respirator with headband straps removed 

(outside view).

Figure E2. Respirator with headband strap removed 

(inside view).

Figure E3. Respirator after mounting and sealing with beeswax to the flat plexiglass plate

(front view).

Figure E4. Respirator after mounting and sealing with beeswax to the flat plexiglass plate

(side view).
Health Hazard Evaluation Report 2010-0044-3109 Page 15

A 40- ppendix F: Member NIOSH Bivariate Fit Test Panel for

 NIOSH Investigation of 3M Model 8000 Filtering

Facepiece Respirator Fit Testing

Number of Test Subjects Tested Per Cell (Red Font)

Testing Started January 15, 2010; Completed January 28, 2010

Figure F1. 40-Member NIOSH Bivariate Fit Test Panel for NIOSH investigation of 3M Model 8000 filtering

facepiece respirator fit testing.

Face Width (mm)

134.5 146.5 158.5 

120.5 132.5 144.5

138.5

128.5

118.5

108.5

98.5

Cell #10

(2) Cell #6 

(3)

Cell #4 

(9)

Cell #8

(4)

Cell #1

(4)

Cell #5

(2)

Cell #7 

(8)

Face Width (mm)

134.5 146.5 158.5 

120.5 132.5 144.5

138.5

128.5

118.5

108.5

98.5

Cell #3 

(4)

Cell #2

(2)

Cell #9 

(2)

Face Length (mm)
Page 16 Health Hazard Evaluation Report 2010-0044-3109

Acknowledgments and

Availability of Report

The Hazard Evaluations and Technical Assistance Branch 

(HETAB) of the National Institute for Occupational Safety and 

Health (NIOSH) conducts field investigations of possible health 

hazards in the workplace. These investigations are conducted 

under the authority of Section 20(a)(6) of the Occupational Safety 

and Health Act of 1970, 29 U.S.C. 669(a)(6) which authorizes 

the Secretary of Health and Human Services, following a written 

request from any employer or authorized representative of 

employees, to determine whether any substance normally found 

in the place of employment has potentially toxic effects in such 

concentrations as used or found. HETAB also provides, upon 

request, technical and consultative assistance to federal, state, and 

local agencies; labor; industry; and other groups or individuals to 

control occupational health hazards and to prevent related trauma 

and disease.

The findings and conclusions in this report are those of the 

authors and do not necessarily represent the views of NIOSH. 

Mention of any company or product does not constitute 

endorsement by NIOSH. In addition, citations to websites 

external to NIOSH do no constitute NIOSH endorsement of 

the sponsoring organizations or their programs or products. 

Furthermore, NIOSH is not responsible for the content of these 

websites. All Web addresses referenced in this document were 

accessible as of the publication date.

This report was prepared by Roland Berry Ann of the National 

Personal Protective Technology Laboratory (NPPTL). Testing, 

evaluation, and document review were provided by Gary Walbert, 

Jim Policastro, Bill Newcomb, Pat Wiltanger, Jeremy Brannen, 

and Jeff Peterson of NPPTL. The NIOSH Respirator Policy Group 

also served as reviewers. Editorial assistance was provided by Jackie 

Krah. Desktop publishing was performed by Robin Smith.

This report is not copyrighted and may be freely reproduced. 

The report may be viewed and printed at www.cdc.gov/niosh/hhe/. 

Copies may be purchased from the National Technical Information 

Service at 5825 Port Royal Road, Springfield, Virginia 22161.
Below is a recommended citation for this report:

NIOSH [2010]. Health hazard evaluation report: NIOSH Investigation of 3M Model 

8000 Filtering Facepiece Respirators Requested by the California Occupational 

Safety and Health Administration, Division of Occupational Safety and Health, 

Oakland, CA. By Berry Ann R. Pittsburgh, PA: U.S. Department of Health and 

Human Services, Centers for Disease Control and Prevention, National Institute for 

Occupational Safety and Health, NIOSH HETA No. 2010-0044-3109.

To receive NIOSH documents or information about 

occupational safety and health topics, contact NIOSH at:

1-800-CDC-INFO (1-800-232-4636)

TTY: 1-888-232-6348

E-mail: cdcinfo@cdc.gov

or visit the NIOSH web site at: www.cdc.gov/niosh.

For a monthly update on news at NIOSH, subscribe to 

NIOSH eNews by visiting www.cdc.gov/niosh/eNews.

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Safety and Health