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Quick answer
When a Gas Safe engineer finds an unsafe gas appliance or installation, they follow the industry’s Gas Industry Unsafe Situations Procedure and classify it. “Immediately Dangerous” (ID) means the appliance is a danger to life or property now; with your permission it will be disconnected and labelled, and it must not be used until repaired. “At Risk” (AR) means one or more faults could become dangerous; the engineer will turn it off with your permission and advise it is not used. “Not to Current Standards” (NCS) means it does not meet today’s standards but is not currently unsafe. You will be given a written warning notice explaining which applies.
Key takeaways
- The three classifications are Immediately Dangerous, At Risk and Not to Current Standards.
- ID: disconnected with your permission, labelled “Do not use”, and must be repaired before use.
- AR: turned off with your permission, labelled, and should not be used until fixed.
- NCS: no immediate action required, but the engineer is advising you of the issue.
- Using an appliance labelled as unsafe is dangerous and, in some circumstances, an offence.
Why engineers use these classifications
Gas Safe registered engineers follow a procedure published by the Institution of Gas Engineers and Managers (IGEM/G/11). It makes sure unsafe situations are handled consistently across the industry, so a householder gets the same message whichever registered engineer visits.
Immediately Dangerous
An appliance or installation is ID when continued use is an immediate danger to life or property. Examples include a gas leak, a flue that is spilling combustion products into the room, or a severely damaged appliance. The engineer will ask your permission to disconnect it from the gas supply and will attach a “Do not use” label. If you refuse, they can contact the gas emergency service provider, which has powers to make the situation safe. The appliance must not be reconnected until the fault is fixed by a Gas Safe engineer.
At Risk
An appliance is AR when one or more faults exist that could become dangerous in future. Examples include inadequate ventilation, a missing flue component or an appliance with signs of poor combustion. The engineer will turn it off with your permission and label it. It should not be used until the fault is corrected.
Not to Current Standards
NCS applies where an installation does not meet current regulations or standards but is not unsafe. Older installations often fall into this category. It is advice, not a prohibition, but it is worth planning to address.
What to do if you receive a warning notice
- Read the notice. It states the classification and the fault found.
- Do not use any appliance labelled ID or AR.
- Arrange a repair by a Gas Safe registered engineer. Check registration at the Gas Safe Register. See checking a Gas Safe engineer.
- Keep the paperwork with your other appliance records.
Landlords and warning notices
If a warning notice is issued during a landlord gas safety check, the landlord must deal with it; a gas safety record cannot show the appliance as safe while it is ID or AR. Tenants should be told not to use the appliance and the repair should be prioritised. See our landlord gas safety certificate checklist.
Book with Gasmaster
Been left a warning notice and need the repair done properly? Gasmaster Plumbing & Heating, Gas Safe registered (220932), carries out boiler repairs and appliance safety work across Stoke-on-Trent, Newcastle-under-Lyme and Biddulph.
Frequently asked questions
Can an engineer turn my gas off without my permission?
The engineer will ask your permission. If you refuse for an Immediately Dangerous situation, they can call the gas emergency service provider, which has powers to make the situation safe.
Can I get a second opinion?
Yes, from another Gas Safe engineer. Do not use the appliance in the meantime.
Does NCS mean my boiler is unsafe?
No. It means it is not to current standards but is not currently considered unsafe.
Sources
- Gas Safe Register, unsafe situations guidance (gassaferegister.co.uk)
- Institution of Gas Engineers and Managers, IGEM/G/11 Gas Industry Unsafe Situations Procedure (igem.org.uk)
- Health and Safety Executive, gas safety guidance (hse.gov.uk)
- National Gas Emergency Service, 0800 111 999
Related services
Abdul runs Gasmaster Plumbing & Heating and has worked on boilers, heating and gas appliances across Stoke-on-Trent since 2005. He is Gas Safe registered (reg. 220932), and these articles come from his day to day work in homes and businesses across Staffordshire, Cheshire and Derbyshire.
