I am caring for my father, who is at home on oxygen (he’s getting one liter per minute, although the machine can be set much higher than that). A home health care nurse told me that my father shouldn’t be in the kitchen when a burner on the stove is lit, and also that we shouldn’t use Vaseline to keep my dad’s lips and nose moist because it’s flammable.
So how hazardous is medical oxygen, really? Would it cause petroleum jelly to spontaneously combust? Is it unsafe to even be in the same room with an open flame?
My wife is on home oxygen and we were never told the bit about Vaseline. The cooking thing, I agree with. My wife has trouble with the cannula coming loose so no cooking for her.
She uses a wheelchair so a loose or falling cannula is right at burner level.
The whole vaseline/oxygen flammability issue is an urban legend based on the fact that said product is combustible. But there’s no credible evidence behind it. Dispelling the petroleum jelly myth
Still, if the patient is a smoker or fire eater on oxygen, I’d avoid petroleum jelly, along with flammable clothing/bedstuff. And don’t grease the equipment with it.
The flash point of a substance decreases in an oxygen-rich atmosphere. Whether it’s sufficiently depressed for petroleum jelly to cause an actual problem, I can’t say, but that’s where the warning likely originates.
Medical oxygen, or any bottled oxygen for that matter, has a very high hazard of fire. It causes what I believe firefighters call flashover, where everything starts burning all at once … the the air is enriched with oxygen so the fires burn hotter … all in all the oxygen should be treated with the utmost care … it does leak out and you can get into deep trouble in a flash …
We do have bottled oxygen as backup, but almost all the time my dad gets his oxygen from a concentrator.
He doesn’t cook - I took over the cooking from him even before he went on oxygen. I certainly wouldn’t let him get near the stove while a burner is on. The nurse told me, though, that he shouldn’t even be in the room while a burner is on, which seems extreme to me. It could be that they tell people things like this with the idea that too much caution is better than too little.
Three things needed for a fire: Oxygen, a fuel source and a means of ignition. The more oxygen there is the more flammable the fuel source will be, but it will not spontaneously burst into flames. However, in the right circumstances, all that is needed is a small spark.
I have seen guys use o2 from welding set ups to accelerate flames on wood, cotton things like that.
This is many times more volume that what you might see from a medical device. It would take quite a bit of O2 to raise the room concentration 1% I would think. A leaky bottle could be very dangerous in a non ventilated room
I measured the kitchen, and its volume is about 1224 cubic feet, or 34660 liters. Air is about 20% oxygen, so there are about 6932 liters of oxygen in the room. Half of this is 3466 liters, which means with a flow of one liter per minute it would take about 3466 minutes to increase the concentration of oxygen by 50% (i.e. from a 20% concentration to a 30% concentration), assuming the room were sealed (it isn’t, of course). That’s about 2.4 days.
Given this, it seems unlikely to me that an oxygen concentrator could fill a room with enough oxygen to make it hazardous. The hazard would be in the immediate vicinity of the canula, which really would be oxygen-rich.
I’m sure an oxygen bottle would be hazardous if the valve were opened without a regulator in place.
If an oxygen concentrator is in the same room as the person using the oxygen, doesn’t the concentrator also output the extracted nitrogen so that the overall balance of gasses in the room remains stable?
That’s a good point. In this case, the concentrator is in the living room, so when my dad is in the kitchen the nitrogen is being emitted in a different place from the oxygen. Still, I would expect diffusion to even things out pretty quickly.
Especially with the use of a concentrator, I can’t see the danger being anywhere but the cannula or any spot the hose may be cut or has a hole. I work in a place with liquid oxygen tanks (3 of them) that vent into the room when they reach pressure (when surgery isn’t using them as much, usually overnight or weekends). Plus, we’re very often running oxygen lines at 10 liters per minute for newly arrived critical patients before we move them to either an oxygen cage or nasal delivery. If all that doesn’t raise the concentration in the room (as our oxygen cages tell us when we turn those on, starting at 21%), there’s no way I can see how a little personal concentrator will.
IMO the issue with medical oxygen in a kitchen is not that it’s going to raise the room O2 concentration.
It’s that when the oxygen user is near a stove, and the cannula falls off his/her ears, and the plastic tube lands in / near the stove fire and melts, then concentrated O2 is being injected directly into an open fire. With major accelerant results. The entire length of plastic tube will probably go up in a flash like a very quick-burning fuze.
You may argue that those individual events aren’t all that likely, much less the entire chain of events. I’d reply that with WAG 10 million Americans using home O2 every day even a one-in-a-million event is going to happen about once per waking hour nationwide.
Liquid oxygen and Vaseline is pretty impressive. We had a science demonstration when I was in Jr. High, a guy with liquid oxygen. He did the shattering rose (dip rose in LOX, break with hammer), but he also did a LOX/Vaseline demo. Took one of those little paper cups like they put mustard/ketchup in in school - the kind you can pull the rim apart and flatten the cup. So he flattens the cup, smears it with Vaseline, adds a couple of drops of LOX and hit it with a hammer. Made an impressive little explosion.
And if you look at the regulators for oxygen service - industrial or medical - there is always a warning to “Use No Oil”, but those regulators are exposed to high pressure oxygen on the tank side.
