Except as provided in this section, you must not require a passenger with a disability to have a medical certificate as a condition for being provided transportation.

You may require a medical certificate for a passenger with a disability—

Who is traveling in a stretcher or incubator;

Who needs medical oxygen during a flight; or

Whose medical condition is such that there is reasonable doubt that the individual can complete the flight safely, without requiring extraordinary medical assistance during the flight.

For purposes of this paragraph, a medical certificate is a written statement from the passenger's physician saying that the passenger is capable of completing the flight safely, without requiring extraordinary medical assistance during the flight.

To be valid, a medical certificate under this paragraph must be dated within 10 days of the scheduled date of the passenger's initial departing flight.

A passenger who schedules a flight from New York to London on January 15 with a return on April 15 would have to show a medical certificate dated January 5 or later. The passenger would not have to show a second medical certificate dated April 5 or later.

You may also require a medical certificate for a passenger if he or she has a communicable disease or condition that could pose a direct threat to the health or safety of others on the flight.

For purposes of this paragraph, a medical certificate is a written statement from the passenger's physician saying that the disease or infection would not, under the present conditions in the particular passenger's case, be communicable to other persons during the normal course of a flight. The medical certificate must state any conditions or precautions that would have to be observed to prevent the transmission of the disease or infection to other persons in the normal course of a flight. A medical certificate under this paragraph must be dated within 10 days of the date of the flight for which it is presented.

As a carrier, you may require that a passenger with a medical certificate undergo additional medical review by you if there is a legitimate medical reason for believing that there has been a significant adverse change in the passenger's condition since the issuance of the medical certificate or that the certificate significantly understates the passenger's risk to the health of other persons on the flight. If the results of this medical review demonstrate that the passenger, notwithstanding the medical certificate, is likely to be unable to complete the flight without requiring extraordinary medical assistance (e.g., the passenger has apparent significant difficulty in breathing, appears to be in substantial pain, etc.) or would pose a direct threat to the health or safety of other persons on the flight, you may take an action otherwise prohibited under § 382.21(a) of this part.