A professional who performs pulmonary-function, lung-capacity, diffusion capacity, and blood-and-oxygen tests to gather data for use by physician in diagnosis and treatment of pulmonary disorders. Responsibilities include:

• Confers with patient in treatment room to explain test procedures.
• Explains specified methods of breathing to patient and conducts pulmonary-function tests, such as helium dilution and pulmonary mechanics (flow of air rate in lungs), arterial blood gas analyses, and lung-capacity tests, such as vital capacity and maximum breathing capacity tests, using spirometer or other equipment.
• Measures expired air, using various analyzers.
• Observes and records readings on metering devices of analysis equipment, and conveys findings of tests and analyses to physician for interpretation.
• May perform blood analysis tests to measure such factors as oxygen and carbon dioxide tensions, hemoglobin saturation and levels, and pH of blood, using blood gas analyzer.
• May measure sweat chloride to test for cystic fibrosis, using computerized analyzer.
• May assist physician in special procedures such as bronchoscopy.