Snag Academy

A smell of gas: what to do, in order

This is the one where the order of the steps matters more than the steps themselves, and where the most natural instinct is the dangerous one.

shutregulatora smell like rotten garlic
The case as a child first sees it in the app.

A child walks into the kitchen and something smells wrong. A bit like rotten garlic. Nobody is cooking.

Most safety advice is a list of things to do. This one is a list of things to do in a specific order, and getting the order wrong is what causes the harm.

The smell is engineering, not chemistry

Cooking gas has no natural smell whatsoever. You could fill a room with it and notice nothing.

The rotten-garlic smell is a chemical called a mercaptan, added deliberately by the gas company in tiny quantities, for exactly one purpose: to turn a human nose into a leak detector. The safety system for the entire gas network is your sense of smell, and it was designed that way on purpose.

Which means noticing the smell is not the moment before the safety procedure. It is the first step of it.

The order

Air first. Open the windows and the door, so the concentration starts falling immediately. Then stop the source: turn the cylinder regulator to OFF. Then call an adult. Then wait outside in the fresh air.

Air comes before the regulator because ventilation starts working the instant you open a window, and because it protects you while you do everything else.

The thing that must not happen

No sparks. That is the whole danger.

Here is the part children (and adults) do not know: a light switch makes a tiny spark every time it moves. So does a fan switch, a doorbell, and the switch on an exhaust fan. In a room with gas in it, reaching for the light is one of the worst things you can do, and it is the most natural thing in the world to reach for.

So: no switches on, no switches off, nothing lit, no matches, no lighter. Open, close the regulator, leave.

The answer

Show the answer

The order in the puzzle: notice → open windows and door → regulator OFF → call an adult → wait outside.

The case is deliberately built so that several orders look sensible and only one is safe. Children usually want to turn the gas off first, which is reasonable but slower to help than simply opening a window.

Talking about it afterwards

Worth rehearsing out loud once, in the actual kitchen, pointing at the actual regulator. A procedure you have said aloud in the right room is one you can still find under stress.

Your child can work this one out for themselves in the app, with the picture running and the wrong answer playing out. It is free, and there is no sign-up. Open this case →

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