Pulmonary Function Testing & Spirometry

Pulmonary Function Testing

Pulmonary Function Testing (PFT) refers to non-invasive tests that measure how well the lungs are working. The breathing tests assess lung performance, determining how well a person moves air in and out of their lungs and how well oxygen enters the blood stream.  The tests measure lung volume/capacity, lung size, rates of air flow and gas exchange. This information can help identify, diagnose and decide the treatment of lung and airway diseases or disorders.  Pulmonary function testing is a common component of medical surveillance exams.

Spirometry - Most Common Type of PFT Testing

NOHS uses Spirometry, the most common type of PFT testing.  Spirometry measures the highest amount of air that can be exhaled after the individual’s biggest possible breath has been taken. This testing is used to measure how fast an individual can move air in and out of their lungs and determines whether the individual’s lung capacity falls within a normal range based on their age, height, health history, weight, race and gender.  For this test, the individual will breathe multiple times, with regular and maximum effort, through a mouthpiece with a tube that is connected to either a computer or spirometer, which measures rate of air flow and estimates lung size.  The entire forced breathing capacity is recorded against time and the results will determine whether the individual’s lung function is normal or abnormal.  The accuracy of test results depends on the individual’s efforts and cooperation.

Pulmonary Function Testing - Necessary For The Workplace

Exposure to substances in the workplace can cause breathing problems or lung damage. When there is a possibility of hazardous airborne materials being released, pulmonary function testing helps employers manage the risk to employees.  Lung health monitoring helps the employer by establishing a baseline of their employees’ lung performance, identifying any existing respiratory conditions and the possibility of developing new conditions. Exposure and/or inhalation of common workplace materials can include:

  • Vapors or gases such as nitrogen oxide, ammonia, chlorine, formaldehyde, sulfur dioxide
  • Smoke or fumes that are often present in furnaces, welding, smelting, plastic or rubber manufacturing
  • Dust particles including but not limited to wood, coal, asbestos, cotton, talc, silica, pesticides, metals, fiberglass, etc.
  • Fumes or mist from exposure to varnishes, paints, pesticides, cleaning chemicals, acids, solvents, oils, etc.

According to OSHA, the most commonly occurring airborne hazards that employers are required to monitor are asbestos, coal dust and silica.


NOHS recommends that companies whose employees are exposed to airborne particulates implement an annual lung health program consisting of PFT/spirometry and when necessary, chest x-rays in addition to the completion of a health history questionnaire. Implementing a lung health program allows employers to reduce potential harm to their employees by the early identification of hazards or problems, and establishing intervention methods when necessary. Annual monitoring and comparing results assists the employer in the determination of whether or not any changes to employees’ lung health have occurred.

Preparations for Pulmonary Function Testing & Spirometry

  • Refrain from smoking for at least one hour prior to testing.
  • Wear comfortable clothing that will not interfere with breathing efforts while testing.
  • Refrain from eating a large meal for at least two hours before testing.
  • Refrain from any sort of exercise 30 minutes prior to the testing.
  • Alert medical technician to any health issues, concerns or current medications.

Let NOHS lessen the frustration, confusion, and liability associated with workplace health programs.