Too much oxygen may be dangerous for some people, particularly those with severe COPD. In an emergency it is useful to alert the emergency care team if this is the case. You may be given an Oxygen Alert Card and a Venturi oxygen mask. This will allow them to limit the amount of oxygen to a safe amount for you.
It is important that you keep this in a place where people can find it in an emergency. Some people keep it near the door of the fridge with a sticker to alert staff , placed on the back of their front door or near the telephone. Just make sure it can be clearly seen. Ask your health care professional for further information.