How to check for a gas leak

Soapy water is the standard test. It is safe, it costs nothing, and it finds leaks that you cannot smell.

How do you do the soapy water test?

Mix a little dish soap into water until it lathers. With the cylinder connected and the valve open, brush or spray the mixture over the valve, the regulator seat and along the full length of the hose.

Watch for bubbles forming. Gas escaping under pressure pushes the soap film outward, so a leak shows as a growing cluster of small bubbles rather than a single one.

What do you do if you find bubbles?

1. Turn off the cylinder valve immediately.
2. Disconnect the regulator and check the O-ring or bull nose is present and undamaged.
3. Check the hose along its whole length for cracks, hardening or splits, especially near the ends.
4. Reconnect carefully, making sure the regulator seats squarely.
5. Repeat the soapy water test.

If bubbles persist after that, shut off the supply and do not use the appliance. Call a qualified gas fitter.

Why must you never use a match?

Because a leak you cannot see is still gas in the air. Bringing a flame to a suspected leak is how a small escape becomes a fire.

There is no version of this test that involves an open flame. Soapy water is the whole method.

How often should you check?

Test every time you connect a new cylinder, which is the moment the seal is disturbed and the most likely time for a leak. Beyond that, a check every couple of months takes two minutes.

What if you smell gas but find no bubbles?

Ventilate the room, close the cylinder valve, and do not operate electrical switches. LPG is heavier than air and settles at floor level, so a leak can pool where your hands are not.

If the smell continues with the valve closed, leave the area and call your supplier or a qualified gas fitter.