Fit Testing (Qualitative and Quantitative)

The fitting characteristic of a respirator is the ability of the mask to separate a worker's respiratory system from ambient air. A fit test is important because this is the best way to determine if a mask fits properly and is working by creating an adequate seal. A properly-fitted respirator helps protect workers from hazardous airborne particles that can lead to illness or disease.

There are two types of fit tests: Qualitative and Quantitative.

Qualitative fit testing is a pass/fail test method that uses your sense of taste or smell, or your reaction to an irritant in order to detect leakage into the respirator face-piece.

Quantitative fit testing uses a machine to measure the actual amount of leakage into the face-piece and does not rely upon your sense of taste, smell, or irritation in order to detect leakage. The respirators used during this type of fit testing will have a probe attached to the face-piece that will be connected to the machine by a hose.

You must be fit tested before you use a respirator in the workplace, and you must be retested at least every 12 months to make sure that the respirator you use still fits you. You must be fit tested with the specific make, model, style, and size of respirator that you will be using.