Foreseeing All Your Safety Needs

Respirator Fit Testing

When are Fit Tests Required?

  • Before the employee uses the respirator for the first time,
  • Whenever the employer or the employee has reason to believe the respirator no longer fits due to facial changes, rapid body-weight changes, new facial scars or similar concern,
  • When the employee experiences a medical condition that impacts or could impact safe respirator use and,
  • Test should be done at least annually.

What Options Does Premonition Provide for Fit Tests?

Premonition provides quantitative fit-tests for employers using the Quantifit controlled negative pressure system by Occupational Health Dynamics.  We believe this equipment provides the most accurate fit test and therefore, is the most protective of employees. 

How Do I Prepare for Fit Testing?

  • Select and purchase the respirators that provide the appropriate level of protection for your application, the appropriate features and an acceptable price point for your operation. Occasionally, an employee will fail a fit test because the respirator is a poor fit. Ensure that you have respirators from at least two manufacturers during the fit tests. Most employees fit size medium, however, you may also purchase a percentage of respirators in small and large, for the small number of employees that can’t fit medium.  (Premonition can provide respirators at the clients request)
  • Please inform your employees that they must be clean shaved for the fit testing.
  • Schedule respirator fit-tests with Premonition

How Does the Quantifit Work?

The Quantifit uses controlled negative pressure to evaluate respirator fit.
During a fit test, the technician removes the filter-cartridges on air-purifying respirators or the supply-hose on self-contained breathing apparatus and replaces these with test adapters; inhalation valves are also removed from the mask or blocked open.  The employee dons the respirator and adjusts it for a comfortable fit.  The employee holds her breath for approximately ten seconds and the technician initiates the test.  During the ten-second fit test, the Quantifit device establishes and maintains a slight vacuum, or controlled negative pressure, inside the mask.  Since the respirator inlets are sealed, all sources of air-leakage into the mask are through the face-to-facepiece seal.  Therefore, the volume of air drawn out of the mask by the Quantifit during this short period of time is equal to the leak rate into the mask through the face-to-facepiece seal.
The Quantifit device interprets the result and provides the technician and the employee with feedback on the result.  The technician leads the employee through this short process five times with slight variations.  When the respirator fits, the overall process is complete in three to five minutes.

How Does the Quantifit Differ from Aerosol-Type Fit Testers Like the Portacount?  Which is Better?

Aerosol fit-testers like the Portacount device measure particles; specifically, they measure the particle count inside the mask and compare it to the particle count outside the mask.  Particle generators or candles are often required.  This measurement technique is an indirect measure of respirator fit and there are errors associated with this measurement technique that devalue the result.  Quantifit uses controlled negative pressure (CNP); it measures the actual leak rate and is a direct measurement of respirator fit.
Overall, Premonition prefers to use the Quantifit because it provides a direct meausre of respirator fit with a more reliable result. 

Interested in Respirator Fit Testing?

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