Your need for oxygen when traveling by car is determined by the altitude of your destination and the potential for air pollution and allergens while you travel.
High altitudes may cause some breathing difficulties and you are likely to need oxygen. You therefore need to plan your route carefully and make sure you have enough oxygen for the journey (stored safely away from any heat supply), or at least know where you can refill the tanks. If you plan to use the car’s electrical system to power the concentrator, you need to check that the battery and alternator can cope with the extra demand.
Air pollution will be worse during peak times and on busy highways. Traveling via quieter back roads at less busy times of day, with the windows up and air conditioning on, should minimize the risk of triggering a flare-up.
It is important to check that you are not traveling through an area of known allergens for you. Try and plan your trip when these allergens are less likely to be present.
Always make sure that your car has recently been serviced and that you have everything you need in case of a breakdown, including a spare tire, a jack, extra clothes and a supply of water.