‘Filtering Out Confusion’: NIOSH answers FAQs on respirator user seal checks

Washington — Seal checks should be conducted every time respiratory protection is used on the job, and employers and workers should ensure the equipment is worn properly so an adequate seal is achieved, NIOSH states in a recently published list of frequently asked questions about user seal checks.

Seal checks can use either positive pressure – the user exhales gently while blocking all exit points – or negative pressure, during which the user inhales sharply while blocking ingress points. The NIOSH resource, titled “Filtering Out Confusion,” offers best practices for performing both types of tests and stresses that users may have to be fit tested for a different respirator model or size if a proper seal is not achieved.

NIOSH notes that not all respirators can be checked with negative or positive pressure and suggests users read the manufacturer’s instructions for performing a seal test.

OSHA requires an annual fit test to “confirm the fit of any respirator that forms a tight seal on the wearer’s face before it is used in the workplace,” and to help determine the best respirator model and size for each worker. A user seal check is not a substitute for a fit test, NIOSH states, and users should only wear respirators for which they have been successfully fit tested in the past year.