FIT TESTING

What does a respirator fit test consist of?

Respirator fit tests commonly consist of testing the sensitivity of bitrex (bitter taste) or saccharine (sweet taste) solutions that can come in vials (ampules) that can be used with an applicator tip that can be inserted into the opening of a nebulizer. The wearer of the respirator then applies a fit test hood and the solution is sprayed into the hood. Other test agents also include isoamyl acetate (banana smell) that tests respirators with organic vapor cartridges and irritant smoke (involuntary cough reflex) that tests respirators with level 100 particulate filters.

OSHA requires qualitative or quantitative fit testing before wearing a respirator on the job. Qualitative fit tests (QLFT) may only be used to fit-test: 

• Negative-pressure, air-purifying respirators, used only in atmospheres where the hazard is at less than 10 times the permissible exposure limit (PEL)
• Tight-fitting facepieces used with powered and atmosphere-supplying respirators

Passing or failing the QLFT relies on the user’s senses using one of four OSHA-accepted test agents mentioned above. Each method uses seven exercises performed for one minute: normal breathing, deep breathing, moving head side to side, moving head up and down, bending over (or jogging in place), talking, and normal breathing again.

Quantitative fit tests (QNFT) can be used to test tight-fitting respirators and involves using an instrument to measure leakage around the face seal and produces a numerical result known as a “fit factor”. There are three OSHA-accepted QNFT test protocols:

• Generated aerosol uses a non-hazardous aerosol such as corn oil generated in a test chamber
• Condensation nuclei counter (CNC) uses ambient aerosol and doesn’t require a test chamber
• Controlled negative pressure (CNP) uses a test that creates a vacuum by temporarily cutting off air

QNFTs use the same seven exercises as QLFTs. It also includes an additional “grimace” test where the wearer smiles or frowns for 15 seconds. A fit factor of at least 100 is required for half-mask respirators and a minimum fit factor of 500 for full facepiece negative-pressure respirators.

How do you perform a respirator fit test?

If you’re wondering how to perform a respirator fit test, it’s easiest and most effective to test using a respirator fit test kit like the ones available from PK Safety. The test takes place in two parts: a sensitivity test and a fit test.

The sensitivity test tests the worker’s ability to detect a test solution. This solution will either be sweet or bitter and dispensed via a nebulizer. If the employee hasn’t had anything to eat or drink, except water, and hasn’t chewed gum in at least 15 minutes, they’ll put on a hood and collar and breathe through their mouth with their tongue slightly out when the solution is administered. They will then let the test giver know when they taste the solution.

The procedure is very much the same for the actual fit test, except that the employee is wearing a respirator. However, during the test the employee will also be doing movements that simulate what they will be doing at work. For example, they will turn their head from side to side, look up and down, bend over at the waist, read from a passage, and breathe normally. If these movements can be done without tasting the solution, they pass the fit test. If not, the kit needs to be removed, the pallet cleansed, and the tests administered again until the proper fit is achieved.

How often is respirator fit testing required?

Fit tests must be done at least annually and additionally when a different respirator is used (size, style, model, or make) and when someone undergoes significant facial changes, such as weight fluctuation or dental work, as this could affect the respirator’s fit. Also, if a worker doesn’t pass the fit test the first time, the test must be re-administered.

Who needs respirator fit testing?

Workers who need to wear a tight-fitting facepiece and ensure a tight seal as part of their job need a respirator fit test. This is true for workers who use respirators in their day-to-day job responsibilities or for workers responding to emergencies. If you’re working in healthcare as a first responder or in the oil and gas, mining, chemical production, or laboratory industries, you almost certainly require fit testing. It’s your employer’s responsibility to fit test respirators and teach employees about respiratory safety and the use of PPE.

A respirator fit test ensures that a worker’s respirator forms a tight seal around their face so that potential breathable hazards can’t enter. This can be especially important for workers with small faces or for those with facial hair who might need to make adjustments or wear different respirators than their coworkers. The test helps determine whether contaminants can breach the seal of a mask.