I just heard Lt. General Todd Semonite, commanding general for the US Army Corps of Engineers, talking about their preparation of New York City’s Javits Center for patient care. He said that they’d improved on the ‘old way’ of having separate oxygen tanks dotted around the intensive care beds (to help COVID-19 patients, in this case). In the Javits Center, he said, there’s now a central oxygen source with piping to all the beds.
He’s head of the USACE, so I assume he must know that this is safe.
But I’m wondering–and assuming that someone here at the Dope can explain—HOW it can be safe. The moment I heard him mention this (on tonight’s Rachel Maddow show), I thought “BIG BOOM.”
But obviously I must be wrong about that. So, how does this work safely??? What keeps it from being highly inflammable?
Every hospital room I can remember seeing in my lifetime has had oxygen piped into it. As long as the system is correctly designed and used it is perfectly safe, much safer than having oxygen tanks all over the place.
That said, when I was a teenager a new hospital opened to much fanfare. Unfortunately they somehow switched the oxygen and nitrous oxide lines in the ER, resulting in a number of deaths. So it can be screwed up…
Oxygen isn’t flammable at all.
It makes other things burn really fast, though. So, as long as you keep it away from “other things,” you are safe. Which is why running it in pipes is WAY safer than having a zillion bottles, each of which could leak or be knocked over.
The technology for plumbing Oxygen lines is incredibly mature - it’s used in every hospital, and many different industries.
Does seem as though there are a lot of ways it could go wrong–the one you mention, and others.
I still don’t see how a spark created somewhere—a piece of metal striking some metallic part of the machinery, maybe?—wouldn’t explode the whole system. Maybe there are no metal parts (PVC piping?) in such a system, for that reason. No metal at all in a system pushing a gas over longish distances seems tough to achieve, but maybe that’s how it’s done…
There’s no way that a spark has enough energy to ignite a stainless-steel oxygen line. There’s simply too much mass, and the metal is too inert (although, it will burn, if you try hard enough).
Quote "*Mr. Anderson ‘said the switched lines were discovered by Dr. Leonard Becker, the hospital’s chief anesthesiologist, when a patient began turning blue after receiving what Dr. Becker thought was oxygen.
This was the first indication that something was wrong, Mr. Anderson said when asked about the delay in discovering the mixup. He said that all other patients who mistakenly received nitrous oxide for oxygen were already blue from lack of oxygen, and thus provided no indication that they were receiving anything but oxygen."
*
You are absolutely on the right track : oxygen is very dangerous and can burn stainless steel pipes down to molten mess and you don’t even need a spark for that to happen; a sharp bend is all that is needed. But that is High pressure oxygen - kind of pressures you see in space ships and chemical plants. In fact pipes and equipment have to go through special cleaning procedures before they can be used for oxygen service.
But at the low pressures seen in medical oxygen (I guess it a few psi at the most), it is quite benign.
Back in the 60s there was a serious explosion that killed several workers in a shipyard. The subsequent inquiry discovered that the men were welding inside the hold of the ship. Welders used piped oxygen and acetylene rather than bottles and air was also piped into the confined workspace.
As is usual with these things, the connections were made different to avoid mix-ups, but Murphy’s law prevails. The air pipe was a larger diameter than the other two, which were left and right threaded. When an apprentice was sent up to connect them, he found that the air pipe was too small for the connector, so he went to the stores and found an adaptor. This meant that instead of air, the workspace was being filled with pure oxygen with the predictable result.
To make a fire, you need oxygen, and something else. The “something else” can be almost anything, though some things will work easier than others. Since, in any given environment, there’s almost always a “something else” available, it’s the oxygen that’s dangerous.
We have a distorted view of oxygen’s reactivity, from living on a planet where it’s a sizeable fraction of the atmosphere. But outside of that very peculiar environment, substances like methane are considered highly stable. You know those science fiction stories with freaky aliens that breathe corrosive gas? From the point of view of most of the Universe, we are those freaky aliens.