Pulmonary function testing (spirometry)

Why is spirometry needed in occupational health?

Spirometry measures how well an employee’s lungs work by evaluating the volume and speed of air they can inhale and exhale. In occupational health, it establishes a baseline for employees who may be exposed to dust, fumes, chemical vapors or other airborne hazards, and monitors for any decline over time. Early detection allows timely intervention — adjusting exposure controls, providing appropriate respiratory protection, or referring for further evaluation — helping prevent occupational lung disease.

When is spirometry required?

OSHA requires spirometry for employees in certain regulated industries with meaningful exposure to respiratory hazards, such as silica, cotton dust, asbestos or other agents covered by specific OSHA substance standards, and for employees required to wear a respirator under a respiratory protection program. Testing is typically required at baseline and then periodically, such as annually, to track changes that may be related to workplace exposure.

How to prepare for spirometry

• Avoid heavy meals for at least 2 hours before testing.
• Do not smoke or use tobacco products for at least 1 hour before the test.
• Avoid vigorous exercise for at least 30 minutes before testing.
• Wear loose, comfortable clothing; avoid tight garments around the chest and abdomen.
• Follow your provider’s instructions on inhalers or other respiratory medications before the test.
• Be ready to follow the technician’s breathing instructions closely — accuracy depends on a full, forceful effort.