Lung Function Tests & Chest X-Rays
Dust and fumes can damage lungs slowly, often with no symptoms until the damage is advanced. Lung function tests and chest X-rays can catch problems early, when it may still be possible to prevent more harm.
- Exposed Workers
- Respirator Users
- Employers
Spirometry
- You breathe in fully and blow out as hard and fast as you can into a mouthpiece connected to a machine.
- It measures FVC (the total air you can blow out) and FEV1 (how much comes out in the first second), and the ratio of the two.
- Results are compared with expected values for your age, height, sex and ethnicity, and with your own earlier tests.
- A falling trend or low numbers can point to obstructive problems (such as asthma or COPD) or restrictive problems (such as scarring).
Chest X-rays
- They show scarring, nodules and other changes caused by dust such as silica and asbestos.
- For some exposures, OSHA requires films to be read by a NIOSH-certified B Reader, a physician trained in classifying dust-related changes on X-rays.
- Results are given in a standard classification so changes can be tracked.
When OSHA requires them
- Silica: workers who must wear a respirator for 30 or more days a year get an exam with a chest X-ray and spirometry, then about every three years. See Silica.
- Asbestos, cotton dust, coal dust and other substances have their own medical surveillance rules. See Medical Surveillance.
- Respirator use requires a medical evaluation to confirm you can wear one. See Respirator Medical Evaluation.
- The employer pays and the exam is done during work hours or at a reasonable time and place.
Getting ready
- Avoid smoking, heavy exercise and a large meal just before the test
- Wear loose clothing that allows deep breathing
- Tell the tech about any recent illness, surgery or medicines
- Follow the coach's directions and try your best on each blow; poor effort gives poor results
- Ask for a copy of your results
Your rights
You are entitled to your test results and a written opinion from the doctor in many programs. You can see your records. See Air Sampling & Exposure Monitoring. Tell your doctor about your work exposures. If a problem appears, ask about reducing exposure and about workers' compensation.
Standards & references
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