Hyperbaric Chamber

How does it feel…
…To get nitrogen narcosis at 50m and not die?

Ralph magazine went through a phase of “what’s it like” stories, and I volunteered to take nitrogen narcosis for the team. Mainly because I had a dive licence and no-one else did. Written in about 2003.


NITROGEN narcosis is what happens when divers go so deep that nitro stuffs up their brain. It’s like being smashed, and the deeper you go, the more smashed you get.

On its own, being narked can’t kill you — but when they’re a few fathoms down, divers can suddenly decide it’s a good idea to give their oxygen to a fish, for example. Confusion, paranoia and outright fear are other common symptoms. In the diver, not the fish.

The safest way to experience nitrogen narcosis — aka “rapture of the deep” — is to take water away so you can’t drown. A hyperbaric chamber is a dry environment that simulates depth pressure, and is often used to help divers with the bends. Or to help Ralph journalists write stories without dying.

Myself and three others crowd onto a bench in the chamber, along with a blown-up balloon and a polystyrene cup of pencils (we can’t use biros, because the pressure would force the ink out). Air is pumped in – fast. By the time we’ve simulated two metres of depth, I’ve popped my ears about 15 times to equalise the pressure and relieve agony. At 10m, the original 11 cubic metres of air has doubled to 22 and the compressed atmosphere is already heating up.

At 22m, the balloon is half its original size. The polystyrene cup is being battered as its tiny air-bubbles shrink. Pressure on our vocal cords makes us all sound like Donald Duck. We embark on a Disney version of “Tie Me Kangaroo Down”.

We’re 35m down and very hot six minutes after leaving the “surface”. I feel like I’ve had five double vodkas, then got into bed with the electric blanket on. The guy operating the chamber tells us to whistle. I can’t; the compressed air has been scrubbed free of moisture. Embarrassingly, I start to giggle.

We hit bottom. There are five atmospheres packed into our little space — the same as 50m underwater. If I somehow stepped outside, the air now compressed into my lungs would expand them to about twice the size of my body. Bad look.

My fellow travellers laugh hard about everything. We note that the balloon resembles a used condom. Hilarious. It feels like last call in a bar full of monkeys. And it’s over 30°C.

A quiz is handed to us through an airlock, but it’s impossible. Nitrogen bubbles are pressing on my nerve endings, slowing down messages. I can’t do maths at the best of times.

If I was 50m under the waves, it would be dark, cold and confusing. I could drown or get the bends. It takes 20 minutes to decompress in the safety of the chamber. I’m not drunk anymore, and I don’t have a hangover. Cool.


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