Smell Gas? How to Identify a Gas Leak and What to Do Next (Step-by-Step Guide)

A gas leak in your home or commercial building is a serious emergency. Whether you’re a homeowner in Camden, a landlord in Westminster, or a facilities manager in Canary Wharf, knowing how to spot the signs—and what to do next—could protect your health, your property, and even save lives.

At Pleasant Plumbers, our Gas Safe registered engineers in London deal with gas safety inspections, repairs, and emergency callouts daily. Here’s everything you need to know to stay safe and act quickly.

A gas leak refers to natural gas escaping from a pipe, appliance, or fitting into an area where it shouldn’t be—usually inside your property. Natural gas is highly flammable and, when inhaled in large quantities, dangerous to your health.

1. Smell

• Gas is odourless, but suppliers add a chemical called mercaptan to give it a distinctive rotten egg smell. If you detect it, act immediately.

2. Hissing Sound

• Listen for hissing or whistling near a gas line, boiler, or hob. This could indicate a high-pressure leak.

3. Headaches, Dizziness, or Nausea

• These are early signs of gas exposure. If multiple people in the property experience them, leave the premises immediately.

4. Dead Houseplants

• Unexplained wilting of indoor plants can point to gas displacement reducing oxygen levels.

5. Bubbling in Standing Water

• If you see bubbles in puddles or soil outside your property, a buried pipe may be leaking.

1. Do NOT ignite anything.
Avoid turning on lights, using lighters, or operating electrical appliances.

2. Ventilate immediately.
Open all doors and windows to disperse the gas.

3. Turn off the gas supply at the meter.
If it’s safe, switch off the emergency control valve (usually located next to your gas meter).

4. Evacuate the property.
Get everyone outside and away from the building.

5. Call the National Gas Emergency Service.
📞 0800 111 999 – Free, 24/7

6. Contact a Gas Safe Plumber in London like Pleasant Plumbers.
Once the emergency service has made it safe, a registered Gas Safe heating engineer in London is needed to repair the fault and check your system.

• Faulty appliances (e.g. boilers, gas cookers)
• Loose or damaged pipe joints
• Old or corroded pipework
• Poor DIY work or unqualified installations

Always ensure your appliances are installed and serviced by a Gas Safe registered plumber in London like Pleasant Plumbers.

Gas leaks are rare with modern appliances—but only if systems are maintained properly. If you're a landlord, you're legally required to have an annual Gas Safety Certificate (CP12). Even homeowners should have boilers and gas appliances inspected every 12 months.

Our team provides comprehensive servicing, certificates, and repairs across Central and Greater London.

If you smell gas or need a gas safety inspection, don’t wait.

📲 Call or WhatsApp 0800 046 1000
🌐 [email protected]

We’re here to keep your home or property safe, efficient, and compliant.

Searching 'Plumber Near Me?' Plumber London or Commercial Plumber London? We operate all across London! If you need a trusted plumber in London then get in touch with us today on 0800 046 1000.

Searching 'Plumber Near Me?' Plumber London or Commercial Plumber London? We operate all across London! If you need a trusted plumber in London then get in touch with us today on 0800 046 1000.