Spirometry in the occupational health setting--2011 update.

S pirometry, the most frequently performed pulmonary function test (PFT), is the cornerstone of occupational respiratory evaluation programs. In the occupational health setting, spirometry plays a critical role in the primary, secondary, and tertiary prevention of workplace-related lung disease.1 Used for both screening and clinical evaluations, spirometry tests are performed in a variety of venues ranging from small clinical practices to large testing facilities and multiple plant medical departments within an industry. Physicians and other health care professionals may conduct spirometry tests themselves or supervise others conducting the tests, or they may be involved only in interpreting test results. Whatever their level of involvement in the actual testing, spirometry users need to be aware that spirometry differs from many other medical measurements, since it depends on multiple factors for its results to be valid. If any of these factors malfunctions, for example, if subject effort is flawed, equipment is not accurate, or technicians fail to elicit maximal cooperation and effort, results can be falsely elevated or reduced. These problems may profoundly impact conclusions that are drawn about a worker’s pulmonary function, and will likely render the interpretations incorrect. Recognizing the central role of spirometry in workplace respiratory programs, the American College of Occupational and Environmental Medicine (ACOEM) developed two spirometry position statements in the past decade which summarize advances of particular relevance to occupational health practice.1,2 However, since these statements were published, several important changes have occurred in the field of pulmonary function testing that significantly affect occupational spirometry testing. First, the American Thoracic Society (ATS) and the European Respiratory Society (ERS) issued a series of joint