Can a person swim/stay afloat in crude oil?

A few years back I worked in the oil field and one set of tanks was very rusted, enough that you could see through the top in places. I had a horrible fear of falling through. I assumed that if I fell into, say, eight feet of crude oil through the top of a tank that I would drown immediately because I would sink to the bottom.

But is that true? Is there any way to dogpaddle in oil? I’d like to ignore the fact that the fumes at the surface would impede my getting much in the way of oxygen and simply deal with the physics of swimming in oil if possible.

The density of crude oil varies with source and temperature, but for quick calculations, 0.8 g/cubic centimeter should suffice.
A submerged 200Lb (90.7kg) person, neutrally buoyant in water would displace (90.7 X 0.8) 72.6 kg of crude. You’d have to supply the force to keep 18.1kg (40 pounds) afloat. You might do that for a short time, but it’d get tiring pretty fast.

jsgoddess, you may want to avoid the movie Wages of Fear.

I was set to bring this up, until I got to the end of your post. Fredetrick Forsyth makes much of the fumes in his suspense novel The Devil’s Alternative, anmd it’s a factor much overlooked. I understand that, even in the absence of petroleum fumes, they pipe the exhaust from the ship’s motors into the containers, so that the atmosphere in there will lack oxygen and prevent any burning or explosion.

A neutrally buoyant person is a person in pretty good physical shape and fairly rare in the US these days. Barring a body builder I once had as a roommate I have never know anyone who couldn’t float just by holding their breath (I float if I hold my breath and sink when I exhale…he could not float at all and had to swim to stay afloat). When I see particularly overweight people they cannot sink at all. I watched a heavyset friend try to swim down to the bottom of a pool once and all he could do was get a foot or two underwater with each stroke as between strokes he bobbed back to the surface.

Still…point taken and great answer. Clearly falling into a vat of crude oil is not a good thing no matter what your physique.

As I’ve recently taken up diving, I can relate. I used up most of the damn, bloody weights the first time I went under. Can’t wait to get back into fresh water, or maybe what I really need is an oil sea.

Yep, I’ve opened the hatch on oil tanks and got completely lightheaded from the fumes pouring out.

Kids, don’t try this at home!

My father and my son both cannot float. They’re not abnormal looking people just very, very dense (as I like to tell them!) My father even has a ginormous beer gut which you think would help him out, but doesn’t. Both of them can take a big lungful of air and sink like a stone. They like to sit at the bottom of the pool crosslegged and grab the ankles of unsuspecting folks walking in the pool. Dense bastards! :smiley:

[nitpick]
They do indeed inert the cargo, however they use boilers, not the engines. A typical crude oil carrier will have two big-ass boilers in the engine room. The flue gas from these boilers is scrubbed, cooled and sent to the cargo tanks with an oxygen content of less than 5%. The cargo tanks are required to have less than 8% oxygen inside.
[/nitpick]