Spirometry is a common type of pulmonary function test (PFT) that measures how well a person can move air in and out of their lungs. In occupational settings, spirometry can be used to establish a baseline before assigning a worker to job tasks that are physically demanding, that require use of a respirator, or that may expose the worker to respiratory hazards. Physicians may also require a PFT as part of the annual respirator certification process.

Accurate spirometry testing, interpretation, and follow-up are critical to effective screening and surveillance of workers exposed to respiratory hazards. Whether spirometry is conducted to comply with an OSHA regulation or as part of another workplace-mandated program, its value is compromised when testing is conducted incorrectly, equipment is inaccurate, or results are misinterpreted.