Suspected gas leak in Macclesfield

The National Gas Emergency Service number is 0800 111 999. It is free, staffed around the clock, and it is the right call whether the smell turns out to be a leak or not. They will attend, make the situation safe and isolate the supply. No plumber, however good, is a substitute for that call.

While you wait: open every door and window you can reach. Do not operate any electrical switch — that includes light switches, doorbells, extractor fans and mobile phones used inside the property, because a switch contact makes a spark. Extinguish cigarettes and naked flames. If the meter is accessible and you can reach the emergency control valve safely, turn it so the handle sits across the pipe. Then leave, and call from outside.

Carbon monoxide is a different danger with different symptoms, and it has no smell at all. The warning signs are a CO alarm sounding, sooty or yellow-brown staining around an appliance, a yellow rather than crisp blue flame, excessive condensation in the room, and headaches, dizziness or nausea that improve when you leave the house and return when you come back. If you suspect CO, treat it exactly like a gas leak: get out, ventilate, and call the same emergency number.

After the emergency service has made things safe, the appliance or the pipework still needs putting right, and that is where a Gas Safe registered engineer comes in. The emergency service isolates; it does not repair. If your gas has been capped off, the supply cannot be restored until the fault is fixed and tested by someone registered to do it.

It is worth knowing that a gas leak is not always dramatic. A very small leak on a joint or a flexible cooker connector can produce nothing more than an intermittent whiff near the appliance. That is still a leak, and it is still an emergency call — the free number exists precisely so that nobody has to weigh up whether it is worth bothering anyone.

One preventable version of this: every gas appliance should be serviced annually, and every home with a gas, oil or solid fuel appliance should have a working carbon monoxide alarm sited according to the manufacturer's instructions. In England, landlords are legally required to have a CO alarm in any room used as living accommodation that contains a fixed combustion appliance.