Space heater safety

Electric space heaters used to have a bad reputation, and rightly so. Manufacturers learned the hard way that the life of a space heater outside of their test laboratories was greatly different to the environment inside their labs.

But now those lessons are learned, space heater safety is back to the level we'd expect in America.

Space heater safety in electric models.
The main space heater safety features developed over the years for electric models are tip-over switches and overheat cut-off switches.

The tip-over switch is designed to turn off the heater if it gets knocked over. When heaters are not upright there is the possibility that the heated elements end up close to your carpet or your furniture, which increases the risk of fire. The tip-over switch automatically cuts off the power for you, thus increasing your safety and reducing the risk of fire.

The overheat cut-off switch works in a slightly different way. If the heater recognizes that the heat it is generating is not getting distributed but is instead backing up into itself, this switch will shutdown the unit.

Which of the features do you want ?
Do you want both ?
Well, the answer depends on your application.
* A heater without an overheat cut-off switch will not notice if your drapes end up in front of it... which leaves you at risk.
* A heater with the overheat cut-off switch but without a tip-over switch will withstand being knocked over so long as the result of the displacement leaves it operating inside of its safety limits.
* A space heater with both switches will shut itself off if it gets disturbed in either way which is excellent for your child's bedroom but not necessarily what you want in an un-carpeted construction area that you don't want to freeze.

So you really have to decide based on your own space heater safety requirements.
Our conclusion, is that a space heater without the overheat cut-off switch should never be left unattended, but as we stated earlier, manufacturers are producing very safe machines these days and any modern space heater should have the over-heat sensor built-in.

Space heater safety in gas models.
Modern vent-free gas space heaters are designed and manufacturered in such a way that they pollute your home at about 2% the speed of a gas stove in your kitchen. The pollution is the by-products of burning your gas (either propane or natural gas).
This is great.
It means that you can run your heater flat out for 2 full days or you can run your gas stove (with the door closed) for 1 hour and generate the same amount of pollution. The rate the pollution is introduced to your home is so low that you are very unlikely to ever notice anything from either device (even the gas stove that pollutes at 50 times the rate of the heater).

But that's the lab with carefully constructed tests.
In the real world we need safety mechanisms to notice when the heater "might" be failing.

The gas space heater safety feature is called the ODS - or Oxygen Depletion Sensor (some people call it Oxygen Depletion Switch). The ODS system is continuously checking the level of oxygen in the room while the the heater is running. If the level falls below its safety threshold, the ODS system automatically shuts off the heater and stops the flow of gas.
If your heater shuts down, it doesn't mean you need to evacuate your home. Far from it, the "safe" level is set by the safety people to be VERY safe, and you as the user probably wont notice any difference inside your home, but you can rest assured know that if the heater had not shut itself off, in time, you may well have.

ODS systems are excellent and have definitely saved lives and brought the gas space heaters into the modern era, but they have their critics. The biggest complaint (from users) about ODS systems shutting off heaters is that the safe levels are too safe.
Cities at higher altitude have thinner oxygen than those at sea level, so the safety switches mean that some people can't even operate their heaters.
Other people have been known to put a heater designed for 1000 square feet inside a 300 square foot room, this also triggers the ODS system because it is expecting the pollutants from the heater to be spreading out into a 1000 square foot room.
As frequently as we hear these complaints they are not a convincing argument for having the safety councils adjust the "safe" levels. If you use a gas space heater in the manner and environment it is designed for, the ODS system can be thought of as your best friend. Its is a tried and trusted technology. It is there for your protection. And it works.

Space heater safety in kerosene models.
The kerosene heaters that are designed for outdoor and construction use are typically designed to be long and low to the ground (with a low center of gravity) - this makes them very hard if not impossible to tip over with fuel inside. And if you do manage it... all models we have seen on the market today have fuel caps so that the fuel is stored away safely.
A lot of the indoor kerosene heaters that used to be available are being withdrawn from the market. You can still see some old inventory in some hardware stores nowadays but we'll leave it to your own judgement if you think it is safe to have spillable kerosene inside your home near an open flame - we certainly don't recommend it.


Back to our home page for an overview of space heaters in general.