Get your medical certificate

If you need additional oxygen on board a plane, you will be asked to provide a medical certificate. Find out how to get one on this page.

Last Update 24/04/2023

If you need additional oxygen on board the plane, your airline will ask for a medical certificate, commonly referred to as a Fit to Fly Certificate or MEDIF (Medical Information Form). These certificates show that you are healthy enough to fly.

All medical certificates are usually composed of two parts to be completed by:

  • the passenger or their carer (usually part one)
  • a doctor (usually part two)

Passengers are usually responsible for signing and sending the form. Always read the instructions on how to complete it, and when and who to send it to.

You will need to give the date or booking reference of your flight on the form.

Where to find it

Each airline has its own form which can be downloaded from their website – usually on the special assistance pages. If it is not online, you will have to contact the special assistance department of the airline (see the airline index for airline contact information).

How to complete it

Only some of the information requested in fit to fly and MEDIF certificates may be relevant for you. These certificates are designed to cover different temporary or long-term conditions, including heart problems, recent surgeries and injuries.

In most medical forms you will find the following sections that are relevant if you have a lung condition:

Escorts or accompanying persons

If you wish to travel with someone, it is important to give details of this person so that you can sit next to each other during your journey.

Oxygen supply

You should indicate the oxygen flow rate you will need on board the plane as prescribed by your doctor.

The information includes:

  • rates in litres per minute
  • flow type (continuous or pulse)

Medical equipment

Portable oxygen concentrators

Most airlines now allow passengers to use their own portable oxygen concentrators (POCs), although only specific models may be allowed.

POCs can provide 1–5 litres of 90% oxygen per minute and have batteries.


Airlines should tell you how many extra batteries you will need to take. This is because you need to have access to oxygen even if your flight is delayed or it lasts longer than expected.