Embedded Files
Respirator Fit Testing is a very important part of a respiratory protection program, ensuring that a respirator forms a proper seal on an individual's face, preventing contaminants from entering the breathing zone. There are two main types of fit testing: qualitative and quantitative. Here's a more detailed look at the procedures:
Qualitative Fit Testing (QLFT):
Principle:
QLFT relies on the user's sense of taste or smell to detect leakage of a challenge agent.
It's a pass/fail test, meaning it determines if the respirator provides an adequate seal, but not the exact amount of leakage.
Challenge Agents:
Saccharin (sweet): A sweet-tasting aerosol.
Bitrex (bitter): A bitter-tasting aerosol.
Isoamyl acetate (banana oil): A strong-smelling vapor.
Irritant smoke: A smoke that irritates the upper respiratory tract.
Procedure:
Preparation:
The employee puts on the respirator and performs a user seal check.
The tester explains the test procedures and the challenge agent.
The tester ensures the employee can detect the challenge agent.
Challenge:
The tester introduces the challenge agent into a test hood or around the respirator.
The employee performs a series of exercises (e.g., normal breathing, deep breathing, head movements, talking).
The tester observes the employee for signs of leakage (e.g., coughing, sneezing, detecting the challenge agent).
Pass/Fail:
If the employee does not detect the challenge agent during the exercises, the test is considered a pass.
If the employee detects the challenge agent, the respirator fails the test, and adjustments or a different respirator are needed.
Advantages:
Relatively inexpensive and easy to perform.
Requires minimal equipment.
Disadvantages:
Subjective and relies on the user's senses.
Less precise than quantitative fit testing.
Irritant smoke can be uncomfortable for some people.
Quantitative Fit Testing (QNFT):
Principle:
QNFT uses instruments to measure the actual amount of leakage into the respirator.
It provides a numerical fit factor, which indicates the level of protection provided by the respirator.
Methods:
Controlled Negative Pressure (CNP): Creates a vacuum inside the respirator to measure leakage.
Ambient Aerosol (Portacount): Measures the concentration of particles inside and outside the respirator.
Procedure:
Preparation:
The employee puts on the respirator and connects it to the testing instrument.
The tester explains the test procedures and the instrument readings.
Challenge:
The employee performs a series of exercises (e.g., normal breathing, deep breathing, head movements, talking).
The instrument measures the leakage of particles or pressure changes inside the respirator.
Fit Factor Determination:
The instrument calculates a fit factor, which is the ratio of the concentration of particles outside the respirator to the concentration inside.
A higher fit factor indicates better protection.
Pass/Fail:
The test is considered a pass if the fit factor meets or exceeds the required minimum for the respirator.
If the fit factor is below the minimum, the respirator fails the test.
Advantages:
Objective and provides precise measurements.
More reliable than qualitative fit testing.
Can be used for all types of tight fitting respirators.
Disadvantages:
More expensive and requires specialized equipment.
Requires trained personnel to operate the testing equipment.
General Fit Testing Considerations:
Respirator Selection:
Ensure the respirator is appropriate for the identified hazards.
Provide a variety of respirator sizes and models to accommodate different facial features.
User Seal Checks:
Train employees on how to perform user seal checks before each use of a respirator.
User seal checks are quick checks to ensure the respirator is properly positioned and sealed.
Frequency:
Fit testing is required:
Before the employee is initially assigned to use a respirator.
Annually.
Whenever there is a change in the employee's facial features that could affect the fit (e.g., weight gain or loss, facial surgery).
Documentation:
Maintain detailed records of all fit testing, including:
Employee's name and date of birth.
Date of the fit test.
Type of respirator and size.
Type of fit test (qualitative or quantitative).
Challenge agent (if applicable).
Fit factor (if applicable).
Name of the tester.
Pass/fail result.
Environmental conditions:
The area for the test should be free of anything that could affect the test.
Facial Hair:
Facial hair that interferes with the respirator seal is not permitted.
Why Seal Checks Are Important:
Respirators rely on a tight seal against your face to prevent contaminated air from leaking in.
Facial hair, changes in facial features, or improper placement can compromise the seal.
Seal checks verify that the respirator is working as intended.
Types of Seal Checks:
Negative Pressure Seal Check:
This check simulates inhalation.
It's used for tight-fitting respirators with filters or cartridges.
Positive Pressure Seal Check:
This check simulates exhalation.
It's used for tight-fitting respirators with exhalation valves.
How to Perform a Negative Pressure Seal Check:
Don Your Respirator:
Put on your respirator according to the manufacturer's instructions.
Ensure it's properly positioned on your face.
Cover the Inhalation Port(s):
For respirators with filters or cartridges, gently cover the filter or cartridge inlets with your palms or hands.
Inhale Gently:
Inhale gently, and hold your breath for about 10 seconds.
Check for Leakage:
If the respirator collapses slightly, and you don't feel any air leaking around the edges, the seal is likely good.
If you feel air leaking, readjust the respirator and repeat the check.
Repeat as Needed:
If you still have a leak, you may need to try a different size or type of respirator.
How to Perform a Positive Pressure Seal Check:
Don Your Respirator:
Put on your respirator according to the manufacturer's instructions.
Ensure it's properly positioned on your face.
Cover the Exhalation Valve:
Gently cover the exhalation valve with your hand.
Exhale Gently:
Exhale gently, and hold your breath for about 10 seconds.
Check for Leakage:
If you feel a slight positive pressure inside the respirator, and no air leaking around the edges, the seal is likely good.
If you feel air leaking, readjust the respirator and repeat the check.
Repeat as Needed:
If you still have a leak, you may need to try a different size or type of respirator.
Important Considerations:
Follow Manufacturer's Instructions: Always refer to the manufacturer's instructions for your specific respirator model.
Perform Checks Regularly: Conduct seal checks every time you put on your respirator.
Facial Hair: Facial hair can prevent a proper seal. Shaving is typically required for effective respirator use.
Fit Testing: Seal checks are not a substitute for a formal fit test, which is required by OSHA regulations. A fit test is performed by a qualified professional to determine the appropriate respirator size and type for your face.
Report Problems: If you consistently have difficulty achieving a good seal, report the problem to your supervisor.
Page updated
Google Sites
Report abuse