IAN HOOTON / SCIENCE PHOTO LIBRARY IAN HOOTON / SCIENCE PHOTO LIBRARY
Peak flow meter use. Man blowing into a peak flow meter to monitor his asthma. This device measures the patient's ability to expel air from the lungs, which is known as the peak expiatory flow rate (PEFR). High readings indicate that the condition is under control and low readings indicate that the airways are restricted.
Model release available. Property release available.