Portable heaters account for a disproportionate share of home fires and the causes are consistent: something too close to the heater, or the heater plugged into something that could not carry the load.
Both are avoidable, and the rules are short.
The clearance rule
One metre of clear space on every side, and above. Not "not touching" — a metre.
That means away from curtains, bedding, sofas, laundry, paper, furniture, pet beds and anything else that can burn. Radiant heat ignites material without contact, and a curtain that drifts in a draught closes the distance you thought you had.
This is the single most important rule and it is broken most often by putting a heater near a bed for the night.
The socket rule
Plug it directly into a wall socket. Nothing else.
No extension leads. A heater draws heavily — often the full rating of a domestic circuit — and extension leads, particularly thin ones and reels, are not built for a sustained load of that size. They heat up along their length, and a coiled reel is worse because it cannot shed heat.
No multi-way adaptors, and nothing else on the same adaptor.
Check the plug and socket are not warm after an hour of running. A warm plug means a poor connection and a poor connection is how socket fires start.
Do not run the cable under a rug or a carpet, where heat accumulates and damage is invisible.
Overnight, honestly assessed
Most manufacturers advise against leaving a portable heater unattended, and the safest answer is not to run one while asleep.
If you are going to, the risk differs by type.
An oil-filled radiator is the safer choice. It has no exposed element, no fan, a lower surface temperature, and it does not blow air across anything. It is also silent.
A ceramic fan heater is less suitable overnight. It heats fast and stops heating the moment it is off, has a hot element behind a grille, and moves air.
Whichever type, it needs: a tip-over cut-out, an overheat cut-out, a thermostat, and a timer set to switch off.
A heater without a tip-over switch should not be used in a bedroom at all.
The features that matter
Tip-over switch, which cuts power if the heater falls. Non-negotiable in any room with a pet, a child or a bed.
Overheat protection, which cuts power if the internal temperature rises — usually because a vent is blocked.
A thermostat rather than just a power setting, so it cycles instead of running continuously.
A timer.
A stable base, wide enough that a knock does not topple it.
Where not to put one
In a bathroom — not unless the unit is specifically rated for it, and portable heaters generally are not.
Where it can get wet.
On carpet or a rug, for anything with a floor vent. Blocked airflow triggers overheat cut-outs at best.
In a doorway or a walkway, where it gets knocked.
Near a child or a pet, unsupervised.
Behind furniture, where the heat has nowhere to go.
The other things worth checking
Never use a heater to dry clothes. Draping anything over a heater is the most direct route to a fire, and it is astonishingly common.
Check the cable for damage before each season.
Test the smoke alarm at the start of the heating season, which is the simplest safety measure available.
Turn it off when you leave the room, every time.
An oil-filled radiator suits sustained, unattended heating better than a fan heater — an oil-filled radiator holds heat and has no exposed element, which is why it is the type to choose for a bedroom. Sizing a heater to a room is covered at Pelonis Guide.
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