Development of a new qualitative test for fit testing respirators

Area of Science:

• Occupational Health and Safety
• Respiratory Protection
• Industrial Hygiene

Background:

• Qualitative fit testing is crucial for ensuring respirator effectiveness.
• Existing qualitative fit tests may require validation with new agents.
• The American National Standards Institute (ANSI) provides draft standards for fit test validation.

Purpose of the Study:

• To develop and validate a new qualitative fit test for respirators using Bitrex as the test agent.
• To compare the performance of the Bitrex qualitative fit test with a saccharin-based qualitative fit test and quantitative fit tests.
• To assess the suitability of the Bitrex test for various respirator models and subject fit.

Main Methods:

• A new qualitative fit test was developed using Bitrex.
• Paired qualitative (Bitrex, saccharin) and quantitative (corn oil aerosol) fit tests were conducted.
• Four models of National Institute for Occupational Safety and Health (NIOSH)-approved half-mask respirators were used.
• Tests were performed on subjects with correctly sized and incorrectly sized respirators.
• Data were analyzed according to ANSI Z88.10 draft standard criteria.

Main Results:

• The Bitrex qualitative fit test demonstrated virtually identical performance to the saccharin qualitative fit test.
• Both the Bitrex and saccharin tests met the proposed ANSI requirements for a valid qualitative fit test.
• The study included a range of respirator fits, from optimal to suboptimal.

Conclusions:

• The Bitrex qualitative fit test is a valid and reliable method for assessing respirator fit.
• Bitrex can be used as an effective alternative test agent for qualitative respirator fit testing.
• The developed Bitrex fit test meets proposed industry standards for accuracy and performance.