The law may be different elsewhere, but EMS agencies here (and in a number of other states that I have knowledge of) do not have a prescription for the medications they carry. What medications (including oxygen) and in some cases how we carry them is regulated by state laws and more specifically by Department of Health Services rules and regulations. Our authority to administer them (and therefore carry them) comes from our medical director and base hospital, not a prescription (which by definition is a written instrument that authorizes a PATIENT to use a medication or treatment). Not saying your state or the OP's state doesn't require a prescription... just saying it is not the norm.
Oxygen is a hell of a drug, but unless I was responding to EMS calls on a regular basis in my POV I would save my money. That being said, you can safely carry oxygen in just about any vehicle. Get a good bag or box that was designed to carry and protect the size cylinder you have.
In NY its not allowed. While we can give asprin to a chest pain pt. it has to be transported to the scene in a certified NY state ambulance or dept. veichle. POVs dont count. O2 is a drug and you are not allowed to carry them personally.
IMHO...leave the meds on the rig. Not so much the dangers of it. But more so a legal stand point. It's a medication, you go around w/ O2 in the back seat you can be charged w/ drug trafficking w/o a prescription in your vehicle. & yes you can be charged w/ out DOT papers or prescription. Depend on how the police feel that day.
Thousands of volunteers carry o2 in there pov's (alot of agencies allow it, always go with what your boss says) and I haven't read/ heard of any LEGAL trouble resulting from it. We leave oxygen in the ambulance 24/7 365 for the last 40 years in 100 degree plus heat. If takes quite a bit more than baking in the sun to have those o2 bottles explode.
and the bag is the best way to go.
All protocols and legal issues aside, if you haul it make sure it's secured. The other guys are right, haul it in a bag for convenience and safety. If something were to knock the head off that tank, you've got a missile in your tool box. Just my $0.02.
I live in BTR and have carried OČ in my PVO off and on over the past 30+ years. It will store just fine in your tool box. The main issue it not to allowing grease, oil, and other contaminate the set. I used the old style Robert Shaw box and never had a problem.
As far as legal. The department has to be aurthorized by the department's medical control (doctor) to use OČ, and they must have a perscription on file with thier supplier, but I know of no law in Louisiana that prohibits qualified medics form carrying OČ in thier POV.