Gas Leak — Immediate Response

Natural gas and LPG (bottled gas) are odourised with a rotten-egg or sulphur smell so leaks can be detected. If you smell gas, act immediately — do not investigate, do not assume it is minor.

⚠️ Gas is explosive. A single spark from a light switch, phone, doorbell, or static electricity is enough to ignite an accumulated gas cloud.

Recognising a Gas Leak

Sign	Detail
Smell	Rotten egg / sulphur odour — even faint
Sound	Hissing or blowing near a gas appliance or pipe
Visual	Dust blowing from soil outside; dead/discoloured vegetation in a dry area; bubbling in standing water
Physical	Dizziness, nausea, or headache with no other cause (gas displaces oxygen)

Immediate Actions — What TO Do

Step	Action
1. Don't touch anything electrical	Do not turn any switch on or off — including lights
2. Extinguish flames	Put out candles, cigarettes, open flames — without using electrical switches
3. Open windows and doors	Do this as you leave to ventilate the space
4. Shut off gas supply	Turn off the gas meter valve (quarter-turn so handle is perpendicular to pipe) — only if you know where it is and can reach it without risk
5. Evacuate	Get everyone out immediately, including pets
6. Leave doors open	Helps ventilate as you leave
7. Move away from the building	At least 50 metres — upwind if possible
8. Call the gas emergency line	From outside or a neighbour's phone: 0800 111 999 (UK) / 811 (US) / your national emergency number
9. Call emergency services	If you believe there is immediate danger, also call 999/911

What NEVER to Do

Never	Why
Turn any light switch on or off	Electrical spark can ignite gas
Use your mobile phone inside	Can ignite accumulated gas — use it only once outside
Ring the doorbell	Electronic — can spark
Smoke or use a lighter	Obvious ignition source
Use any electrical appliance	Fans, extractor hoods, appliances all spark
Re-enter the building	Until emergency services confirm it is safe
Assume the smell will clear	It may indicate a serious ongoing leak

Shutting Off the Gas Meter

The emergency control valve (ECV) is usually next to the gas meter — often in a cupboard, under the stairs, or outside in a meter box.

Step	Action
Locate	Find the handle on the incoming pipe — it is inline with the pipe when open
Turn off	Rotate the handle 90° so it sits perpendicular (across) the pipe
Confirm	The handle should now point across the direction of gas flow — gas is off

If you cannot locate the meter or are unsure, evacuate and let the gas emergency service shut it off.

Outside Gas Leaks

If you smell gas outside (in the street, garden, or public area):

1. Do not attempt to locate the source
2. Keep people away from the area
3. Do not smoke or use naked flames nearby
4. Call the gas emergency number immediately
5. Keep vehicles away — engines can ignite gas

When Can You Return?

Only return to the building when:

• The gas emergency service has attended and declared it safe
• The leak has been confirmed stopped and the space ventilated
• You have been given explicit clearance by emergency services

Quick Reference

Situation	Action
Smell gas indoors	Do not touch switches; extinguish flames; open windows; evacuate; call gas emergency from outside
Cannot find gas meter	Evacuate immediately; call gas emergency line
Gas smell outside	Keep clear; call gas emergency; no flames or engines
Someone feels dizzy indoors	Gas may be accumulating — evacuate everyone immediately
Re-entry	Only when gas emergency service gives all-clear
UK gas emergency number	0800 111 999 (free, 24/7)