What is the purpose of fit testing for N-95 masks?

The purpose of fit testing for N-95 masks is to guarantee a proper seal and fit. This process is critical because N-95 respirators are designed to filter out at least 95% of airborne particles, including large respiratory droplets and smaller aerosol particles, as long as they fit snugly against the wearer's face. A proper seal ensures that air inhaled passes through the filter material rather than around the edges of the mask, thus maximizing the protective function of the respirator.

It's important for healthcare workers and others who may be exposed to infectious agents to have an adequately fitting mask to reduce the risk of inhalation of contaminants. Effectively, fit testing confirms that the mask forms a tight seal, which is essential for the respirator to provide the intended level of protection against airborne diseases. This procedure typically involves various methods to assess if there are any leaks when the wearer performs movements, which are intended to simulate normal activities while wearing the mask.