If you can smell gas right now, do not call us first. Call the National Gas Emergency Service on 0800 111 999 immediately. The line is free, runs 24 hours a day, and dispatches a network operator (Cadent Gas across north, east, and central London; SGN across south London) who will isolate the supply at the meter and make the property safe at no charge. Leave the building, open windows and doors, do not switch any electrical equipment, and stay clear until they arrive. The National Gas Emergency Service is the statutory first responder to any live gas escape in the UK and the only party authorised to cut the supply at the meter on their own initiative.
Our role is what comes next. Once the property is safe to re-enter, you need a Gas Safe registered engineer to locate the leak source inside the property, repair the pipework or appliance, soundness-test, and recommission the supply, work that falls outside the network operator's remit. We attend across every London postcode under Gas Safe Register #972173, typically within 60 minutes of the property being made safe, carry a digital manometer for tightness testing at 21 mbar to BS 6891, and document every step on a GIUSP record. We will also walk you through the location of your ECV so you can isolate the supply yourself next time.
Where this service applies
- Follow-up repair after the National Gas Emergency Service has isolated the meter (their notice will state "refer to a Gas Safe engineer")
- Inability to locate the emergency control valve in the meter cabinet, basement, or under-stairs cupboard
- Seized or damaged ECV lever that will not rotate the full 90 degrees from open to closed
- Need to isolate a single appliance branch without shutting off the whole property, requiring a downstream lever valve
- Tenant safety briefing on ECV location, recommended at every change of tenancy and required for HMO licence files
- Commercial premises and HMOs requiring labelled isolation points and a written gas isolation procedure
- Recommissioning the supply after a leak repair, planned works, or a long property vacancy
- Installation of a remote-actuated solenoid shut-off valve linked to a CO alarm in vulnerable-occupant properties
How we deliver
No surprises, no upselling. The exact path every job follows.
- 1
Confirm the property is already safe
If gas is still present we instruct evacuation and confirm 0800 111 999 has been called. We do not enter a property with an active escape until the meter has been isolated by the network operator. - 2
Locate the emergency control valve
Per BS 6400 the ECV sits at the inlet to the meter on the consumer's side, typically in the external meter box, an under-stairs cupboard, or a basement cabinet. We mark it with a yellow ECV label so future occupants and emergency services find it instantly. - 3
Isolation procedure
ECV lever rotated 90 degrees to closed (crosswise to the pipe). Each downstream appliance isolator turned off in sequence. Pilots confirmed extinguished, electrical ignition disabled at the appliance fuse spur. - 4
Source identification with calibrated equipment
Digital manometer on the meter outlet for a let-by and tightness test at 21 mbar, electronic gas detector (sniffer probe) on visible joints, soap solution on suspect compression connections. - 5
GIUSP classification and customer briefing
Defect classified Immediately Dangerous, At Risk, or Not to Current Standards under the Gas Industry Unsafe Situations Procedure. Customer briefed in plain English and a written warning notice issued. - 6
Repair, replacement, or downstream isolator fit
Defective joint or branch repaired in 15 mm or 22 mm BS 6891 copper. Where the customer wants single-appliance isolation, a full-bore lever valve is fitted upstream of the boiler, fire, or cooker. - 7
Recommission under controlled re-pressurisation
Post-repair tightness test with zero permissible pressure drop, ECV opened slowly, each appliance purged, burner pressures verified, FGA readings logged on every appliance brought back into service. - 8
Written report and occupant briefing
GIUSP record, repair certificate, and ECV location diagram emailed same-day. Occupant walked through the ECV, the 0800 111 999 number, and the four-step procedure: evacuate, call, ventilate, do not switch.

