The wonder of lightweight and portable devices is that you can get out of the house and keep active, however it is medical equipment containing a gas that aids combustion, so safety precautions should be taken for your own safety.
• It is recommended that you carry a copy of your documentation with you such as your Medical Oxygen Data Sheet.
• Inform your car insurance company that you intend to carry oxygen in your car.
• Keep the car well ventilated, open a window and set the ventilation to take in air from outside.
• Do not smoke or allow others in the car to smoke.
• Never transport the liquid oxygen mother unit container in the car.
• If possible carry your spare cylinders securely in the boot of the car. Use a cargo net to secure them properly.
• Remember to also secure the ambulatory cylinders or portable liquid flask in your car to prevent any harm coming to passengers or to the vehicle.
• Keep the amount of oxygen that you transport to a minimum and don’t transport large, high capacity cylinders in the car.
• Instead of placing the equipment loose on the back seat, strap it into the seat with a seat belt or place securely in the foot well in the back.
In summary remember that if loose the equipment could shift or move and damage the car, the passengers or the equipment itself so secure it well.
Also due to oxygen’s ability to aid combustion you need to keep the car well-ventilated in case of a leak to prevent a build-up of the gas within the car and to not smoke around it.
Carry documentation in case of an accident as if you are unconscious the emergency services could then be made aware of it’s presence and also of your medical need for oxygen which could save your life.
References: http://www.bochealthcare.co.uk