How do you detect carbon monoxide indoors?

Quickly detecting carbon monoxide (CO) as soon as it diffuses into a room can literally save lives. In fact, in an accident involving a combustion heater that emits this gas, every second counts to avoid carbon monoxide poisoning. So, how can you detect CO as quickly as possible and limit the risk it poses, especially in winter? It all comes down to effective home safety.

Why keep a close eye on carbon monoxide levels at home?

Carbon monoxide: a poisonous gas that can be fatal

Carbon monoxide is a poisonous, odourless, colourless, non-irritating, and potentially fatal gas. It’s heavier than air, which means that it mixes with the air in the room. People who are exposed to CO can’t sense its presence until they feel symptoms.

It’s impossible to see, smell, taste or notice this dangerous gas without a suitable CO detector device. For this reason, CO still causes severe home safety issues.

What exactly is CO?

To understand carbon monoxide poisoning, it helps to know a bit about this gas. Carbon monoxide is a molecule that is also known as CO, because it is made up of one carbon atom (C) and one oxygen atom (O).

This molecule is most often mentioned in the context of its gas form, and in relation to home safety risks. CO is sometimes called the "silent killer" because the harmful gas kills mammals (including humans) without giving any sign of its presence.

Carbon monoxide is produced when a combustion appliance (home heating that runs on wood, oil, gas, etc., for example) or a household appliance malfunctions due to being old and worn out, having a blocked exhaust or being used improperly.

Inhalation of carbon monoxide causes poisoning, which can cause lasting damage to the vascular and pulmonary systems in the short and medium term.

Several methods exist to reduce the risks associated with CO. First, make sure you’re well informed of the dangers CO poses, as well as the signs that it’s present in the home. Know what the symptoms are, and the factors that should alert you to take action. Know how to correctly install your CO gas detector, too, in every room where you have a combustion appliance.

Carbon monoxide has long been known to be dangerous, but it does still cause poisonings every year.

Recognise the signs of carbon monoxide

Recognisable symptoms, depending on the context

The first symptoms appear after only a few minutes of exposure to carbon monoxide. This gas causes asphyxiation-type poisoning, which is different from other types of poisoning.

Some of the recurring symptoms that should alert you to possible carbon monoxide poisoning include headaches and stomach aches, blurred vision, difficulty breathing, dizziness and even fainting, which can lead to death within an hour.

Another sure sign is that you no longer feel the symptoms when you leave the room, but as soon as you return, they return.

If you are in a poorly ventilated room, it’s cold outside, your heaters (especially an auxiliary heater for example, or a gasoline or coal appliance) are running at full capacity and you start to feel these symptoms, there’s probably carbon monoxide present.

When several of these symptoms are triggered simultaneously and the context makes you think there might be CO present, quickly get out into the fresh air and call 999. You’re probably the victim of carbon monoxide exposure, which results in poisoning. You may even have to think about first aid measures: it can be seriously urgent.

Unusual humidity in the room

Traces of moisture can be another sign of the presence of CO. Unusual condensation on a window, or on a table, may indicate that carbon monoxide is building up in the space.

Unusual humidity in a room is a pretty rare indicator of unsafe CO levels, but if you do notice it (and you’re also experiencing physical symptoms), you should be concerned. One of your home heaters may be malfunctioning, you could be experiencing exposure to carbon monoxide, and poisoning could occur within a short time period.

Suspicious light signals on combustion devices

There are also light signals that can help you detect carbon monoxide. Keep an eye on the pilot flame on your gas stove, water heater or other household appliance. If it goes out frequently, glows strangely or weakens, the presence of carbon monoxide may be the cause.

Again, this is not an explicit signal and there may be different explanations for it. But, just like with unusual humidity, you’ll need to stay alert and look out for the combination of several signs or exposure symptoms.

Are carbon monoxide detectors the most effective solution against poisoning?

The carbon monoxide detector is arguably the best way to prevent poisoning and quickly detect CO emissions. As is often the case with poisonings, just like with illnesses, prevention is preferable to treatment.

What is a carbon monoxide detector?

These detectors are used by more and more people to improve safety in their homes. CO detectors can be found in most home improvement or DIY stores, or on the Internet. They’re affordable devices, with detector models to suit all price ranges.

A CO detector is just a small box with a carbon monoxide sensor and an alarm inside. As soon as the safe carbon monoxide threshold in the room is exceeded, a chemical reaction in the detector creates an electric current, which then sounds an alarm.

When placed in every room containing a combustion device, these detectors are very effective. They ensure you’re alerted to the presence of CO well before you feel the first symptoms of carbon monoxide poisoning, so you can take appropriate measures and get to safety.

How do I install a carbon monoxide detector to prevent carbon monoxide poisoning?

For it to be useful, a carbon monoxide detector must be installed in the right place in your home, so that it continuously analyses the ambient air and detects the slightest presence of CO gas.

Ideally, you should place your CO detector in the room with your fuel appliance, between 1 and 3 metres from the appliance itself. The CO detector should be installed on a wall, at eye level. It doesn't need to be professionally installed - the right installation information is all it takes!

One final tip: a room's ventilation should never be obstructed, especially if it is close to potential sources of carbon monoxide.

Installing a CO detector at home is a smart plan of action, given it’s the best solution for detecting carbon monoxide. It ensures your peace of mind and home safety, always alerting you to the slightest problem. Remember, even if you don't use a combustion device that may emit carbon monoxide, you could also be affected by a neighbour's device if you live in an apartment building.