Making an appliance safe: Immediately Dangerous and At Risk

Note 10 of 15 · free to read

What Immediately Dangerous and At Risk mean, which one a failed combustion check gets, and the exact steps each category requires.

Key points

Immediately Dangerous means a danger to life or property right now if the appliance stays connected; At Risk means a fault that could become dangerous later.
An unresolved failed combustion check is ID on a flueless appliance and AR on a flued one, unless another finding establishes immediate danger. Obtain manufacturer advice for the isolated CO2 exception.
With permission, disconnect and seal an Immediately Dangerous appliance; if refused, still try to turn it off and contact the Gas Emergency Contact Centre or LPG supplier.
Turn off an At Risk appliance at its isolation valve, or remove the fuse, or turn off the appliance control; never a room thermostat or timer.
Every At Risk appliance turned off gets a DANGER DO NOT USE label and a signed written notice; refusal to sign or turn it off is recorded, not ignored.

Two categories, not a scale

The unsafe-situations procedure sorts a faulty appliance into one of two categories. Immediately Dangerous means the appliance or installation is a danger to life or property right now if it stays connected. At Risk means one or more faults are present that could turn into a danger later, but are not an immediate one. A shortfall against current standards that you have judged safe is not part of this procedure: record it as advice.

Which category a failed combustion check gets

A confirmed failed combustion-analyser result on a flueless appliance is Immediately Dangerous. On a flued appliance it is At Risk. A failed spillage test or established leakage of combustion products into the room is a separate Immediately Dangerous finding; a working burner or a good-looking ratio cannot cancel it. The same flueless/flued split applies to visible incomplete combustion at the burner or heat exchanger, with evident spillage raising the flued case to Immediately Dangerous. If CO2 is outside its required range without adversely affecting CO, ask the appliance manufacturer for advice, as the procedure says: an out-of-range CO2 reading on its own is not the same fault.

Making an Immediately Dangerous appliance safe

Try to put the fault right and leave the appliance working safely before you go, with the user's agreement.
Where that is not possible, tell the user the appliance is Immediately Dangerous, why, that it must not be used, and that it must be disconnected until the fault is fixed.
With the user's permission, disconnect and seal the gas supply using a proper fitting.
If disconnection is refused, try to turn the appliance off. Immediately call the Gas Emergency Contact Centre for natural gas, or the LPG supplier for LPG. Record the job reference and the time of contact; do not leave the call to the user or a later service visit.
Fit a DANGER DO NOT USE label prominently on the appliance, with an additional visible label on its enclosure if it is concealed.
Give the responsible person a written warning notice describing the defect, action and restriction on use, and keep a copy. Request their signature and record a refusal or absence. If they are not the owner, also provide the owner with the written details.

Making an At Risk appliance safe

Explain to the user that the appliance is At Risk, why, that it could become dangerous at any time, and that it must not be used until the fault is fixed.
With permission, turn the appliance off using its isolation valve first; if that is not possible, remove its electrical fuse; if that is not possible either, turn off the appliance control. Removing a fuse or using the appliance control stops operation but is not physical isolation of the gas supply. Never rely on a room thermostat or a timer, since either can switch the appliance back on.
Attach a DANGER DO NOT USE label to the appliance in a visible position, and to a hidden appliance's enclosure as well.
Complete a written notice headed DANGER DO NOT USE, get the user's signature, leave them a copy and keep one yourself.
If the user refuses to let you turn the appliance off, or refuses to sign, record that detail. If the user is not the owner, also write to the owner.

After the visit

For an unsafe appliance whose risk is reduced by turning it off, leave a visible warning label and a written notice explaining the fault and action taken. A spoken warning, or a label without the notice, is not enough. There is a separate At Risk route for some installation defects where turning off cannot reduce the risk: refer the defect to the responsible organisation and document it without attaching a DANGER DO NOT USE label.