United Airlines now requires all passengers to self-certify their health prior to boarding a flight.
The airline is the first major U.S. carrier to require all passengers to complete a health questionnaire to screen for the coronavirus as part of checking in.
It asks passengers to certify they have not experienced coronavirus symptoms in the last 14 days nor tested positive for the virus in the past 21 days.
It also requests passengers agree to wear a face mask during the flight, which is an airline policy, but not a federal requirement.
There are no current U.S. government or industry-wide requirements for this broad type of health screening.
The airlines have asked the Transportation Security Administration to conduct temperature screening of passengers, but so far the agency has not decided to do so.
Health screening has been conducted by government entities at some airports, particularly for incoming international passengers.