Lung Health News, Fall 2002 / Winter 2003
Flying on a commercial airplane can sometimes leave you feeling lousy. Your nose gets stuffed up and your throat feels dry. But can it actually make you sick?
Air quality inside commercial airliners is a hot topic these days. To address the concerns of airline cabin crew and passengers, the American Society of Heating, Refrigerating and Air- Conditioning Engineers (ASHRAE) is working on a standard for air quality in commercial aircraft.
"We need to have health-based standards," says Fran Du Melle, senior vice president for program services at the American Lung Association’s office in Washington, DC. "Too often these standards are comfort-based only, and we need to consider the health of all people, including people with lung disease and allergies."
A first draft of Standard 161P, Air Quality Within Commercial Aircraft, could be ready for public review by year-end. It is expected to address cabin pressure, air exchange rates, temperature, and humidity.
Airlines Use Recycled Air
Airlines use recycled air in the passenger cabins. Older aircraft tend to filter air and mix in fresh air before recirculating it in the cabin while most newer aircraft use almost all recycled air.
The air is extremely low in humidity and can dry out the mucous membranes in the nose, mouth, throat and bronchial tubes, which are then less able to keep out viruses and bacteria. Airline cabin air is also low in oxygen relative to fresh air on the ground. Healthy individuals shouldn’t notice a difference, but people with chronic lung diseases like asthma and emphysema might.
Most of the newer airplanes use system-wide HEPA filters that remove nearly all fine particles from the air, including airborne bacteria and viruses. But many older models don’t.
Communicable Diseases Can Spread
Some frequent fliers insist flying makes them sick, and health experts agree infectious diseases can be spread on airplanes. For example, there are documented cases of passengers testing positive for tuberculosis (TB) after flying with infected passengers. However, according to the World Health Organization, there is no documented case of anyone contracting active TB on an airplane and the risk of that happening is extremely small because it usually requires repeated exposure to an infected person.
"You are always at risk of catching something, especially on flights more than eight hours long," says Lee Reichman, MD, MPH, former president of the American Lung Association and a renowned expert on tuberculosis. "You can catch infectious diseases on airplanes because the air is being recirculated and because you are in close proximity to others."
The biggest risk may be sitting close to other passengers who are sick. Viruses can survive for short periods in the air and on surfaces like tray tables, seat backs and arm rests of airliners, say officials at the Centers for Disease Control and Prevention (CDC).
"It’s like any enclosed space," says the CDC’s Barbara Reynolds. "The fact that you have germs in close proximity with other people means there will be an exchange."
To reduce your risk of getting sick, wash your hands frequently with hot, soapy water while flying. If possible, don’t sit next to passengers who are coughing and sneezing.
Safe Flying for People with Lung Disease
While even healthy people report discomfort when flying on commercial aircraft, people with lung disease are at greater risk. Because oxygen levels are lower, those who don’t require supplemental oxygen on the ground may need it while in flight.
"The lack of humidity in the air can also be a real problem for people with lung disease," Du Melle says.
Another concern is ozone, which is sometimes present in airline cabins at elevated levels. Ozone irritates the lungs and can pose serious health risks for people with lung disease.
Safe Flying for People with Lung Disease, published by the California Thoracic Society and the American Lung Association of California, offers important information for people with lung disease. You can get a copy by calling your American Lung Association at 1.800.LUNG.USA or visiting www.thoracic.org/ca.html.
"The new standards need to accommodate people with lung diseases and other chronic illnesses," says Du Melle.
