Guide
Unsafe situations: ID, AR and NCS explained
The classification decides what you do next, what you leave behind, and what you say to the customer. Getting it right with someone stood watching you is the pressure, and the categories are narrower than people remember.
Immediately Dangerous
An installation that is, or is likely to become, a danger to life or property if it is used. The appliance comes off gas. With the customer's permission you turn it off, disconnect it or cap it, label it, and issue a warning notice. Where you cannot isolate it, or permission is refused, the situation escalates rather than ends: make sure the customer understands the danger in terms they cannot misread, and follow the escalation route.
At Risk
One or more recognised faults that could cause a danger. You are not automatically isolating here. You turn the appliance off with permission, label it, record it on a warning notice, and advise on the remedial work needed. The distinction from ID is whether the danger is present or potential, and that judgement is yours on site.
Not to Current Standards
Work that complied when it was carried out but would not be installed that way today. Worth knowing: IGEM/G/11 Edition 2 removed NCS as a formal Warning Notice trigger. It is now a note in the paperwork rather than a classification that drives a notice. If you learned this before Edition 2 came in, this is the bit that has changed under you.
RIDDOR does not follow automatically
A common misreading is that an Immediately Dangerous finding is itself reportable. It is not. RIDDOR applies to a dangerous gas fitting incident where someone died, lost consciousness, or needed hospital treatment. Where that has happened, notify HSE by phone within 2 hours and submit the online report within 14 days, and that still applies if you repaired the fault on the same visit.
The bit that is hard on site
None of this is difficult to read in a classroom. It is difficult at 4pm in a kitchen with a customer who wants their hot water back, when the thing in front of you does not match the example you were taught on. The categories are a judgement, and the judgement is yours.
The app
Tap through what you found, get the classification
Flint has an unsafe situations tool: pick the category, answer a couple of questions about what is actually in front of you, and get the IGEM/G/11 classification with the required action numbered in the order you do it, plus a flag when the incident is RIDDOR-reportable. It is a paraphrased summary written for speed on site, not the standard itself, and the classification is still yours to confirm before you leave.
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Common questions
What do ID, AR and NCS mean?
Immediately Dangerous means an installation that is, or is likely to become, a danger to life or property if used. At Risk means one or more recognised faults that could cause danger. Not to Current Standards describes work that met the standards when it was done but would not be installed that way now.
Is NCS still a warning notice category?
IGEM/G/11 Edition 2 removed NCS as a formal Warning Notice trigger. It is now a paperwork note rather than a classification that drives a notice.
When is a gas incident RIDDOR reportable?
RIDDOR reporting applies where a dangerous gas fitting incident caused death, loss of consciousness, or required hospital treatment. It does not follow automatically from every Immediately Dangerous finding.
Flint is a reference tool for competent, Gas Safe registered engineers. Everything here informs your judgement and never replaces it. Always work to the manufacturer's instructions and the current standards, and check every figure against the appliance data badge and manual.