How do I recognise carbon monoxide poisoning?

Carbon monoxide (CO) poisoning is often more frequent during the winter period: it’s also the leading cause of poisoning in industrialised countries, such as the UK. Given that it causes some 60 deaths in England and Wales each year, it’s important to have all the information you need to recognise the symptoms of carbon monoxide poisoning and react in the event of an emergency. This allows us to take action as quickly as possible and can help limit its impact on our health. Prevention of high CO levels is also essential when it comes to ensuring safety in the home.

What are the causes of carbon monoxide poisoning?

Carbon monoxide poisoning can affect anyone who uses wood, gas or petroleum-based heating. Stoves, water heaters and braziers can also produce this highly toxic gas, which can lead to heart problems, brain injury, and even loss of life. Combustion heating is the culprit, specifically when the appliance has a ventilation or installation fault.

For poisoning to occur, carbon monoxide first has to be released. This happens during a process of incomplete combustion when burning the fuel in question. This causes a chemical reaction, which leads to the release of this very dangerous gas. Causes of high carbon monoxide levels include poorly maintained ducts, ageing appliances, blocked ventilation or even improper use of heating. The gas then diffuses into the room, mixes with the air and fills the accommodation. Unlike smoke, it does not rise. This is the situation in which carbon monoxide poisoning takes place.

Anyone who is exposed to the gas is then at risk. Carbon monoxide replaces oxygen in our blood within a very short time period, which can cause a variety of symptoms and result in heart problems and brain injury. Exposure to the gas can even lead to death within an hour, so a high level of CO in a room should be treated as an emergency. More specifically, the carbon monoxide produced during incomplete combustion is inhaled by an individual and attaches to the hemoglobin in their red blood cells (these carry oxygen in the blood). This then prevents these cells from properly transporting oxygen around the body, leading to asphyxiation with multiple consequences including neurological problems and heart damage.

Carbon monoxide poisoning can result in injuries requiring hospital treatment (such as hyperbaric oxygen therapy), or even loss of life. To avoid the health risks linked to carbon monoxide as much as possible, it’s vital to install a carbon monoxide detector. Preventing exposure to dangerous carbon monoxide levels is better than having to seek medical care!

If you have the slightest doubt about possible carbon monoxide poisoning, immediately ventilate the room, turn off any appliances that are burning fuel and contact 999.

Symptoms, dangers and risks of carbon monoxide poisoning

Within the first few minutes of exposure to the gas, the person experiences the initial symptoms of carbon monoxide poisoning. The health effects become more severe as the duration of exposure increases (in other words, as carbon monoxide spreads through the blood and replaces oxygen).

The first symptoms of poisoning include headache, dizziness and nausea, as well as vomiting, blurred vision, shortness of breath or stomach pain.

So carbon monoxide poisoning causes real discomfort, which can have serious consequences for our health. The situation can worsen as the exposure time increases, causing long-term health problems requiring medical attention.

In the most severe cases, if the person remains exposed to the gas, they risk unconsciousness and even death after about an hour. Many poisonings occur during the night, with victims becoming intoxicated in their sleep and never waking up.

Carbon monoxide poisoning is therefore a very real danger in the home, especially in winter. During the colder months, people tend to use more heating appliances and lower the levels of ventilation in their homes, increasing their risk of exposure. Fortunately, precautions can effectively guard against the risks of carbon monoxide poisoning.

Poisoning can lead to neurological problems in the medium term, although these are thankfully often reversible with the proper medical care. Affected patients may suffer from irritability or memory impairment.

How can I avoid carbon monoxide poisoning?

Luckily, cases of carbon monoxide poisoning are falling overall. There are multiple reasons for this:

Better and more reliable devices
More communication on the subject and awareness of the precautions to be taken
The more widespread use of carbon monoxide detectors

Take preventative measures against carbon monoxide poisoning (and against other toxic gases)

When poisoning has started, it is often too late to stop your health being affected, even if the effect is mild rather than severe. It’s therefore better to take preventative steps, to avoid the release of carbon monoxide in the home as much as possible.

Several actions are effective in preventing carbon monoxide poisoning (and poisoning from other gases):

Have heating devices and household appliances checked and maintained every year by a qualified professional
Make sure you ventilate your house for at least ten minutes every day
Avoid leaving your space heaters running continuously
Place generators outside the home
Ensure that vents, air outlets or inlets and ducts remain in good condition and aren’t blocked
Replace ageing devices with new, more reliable ones
Know the first symptoms of poisoning and be ready to react if in doubt

Install a carbon monoxide detector to limit the risk of carbon monoxide poisoning

Since carbon monoxide is a colourless, odourless, non-irritating and therefore completely invisible gas, it’s impossible for people to notice its presence without the help of a device. Once carbon monoxide is present in a room, anyone there will feel its effects rapidly. Fortunately, carbon monoxide poisoning is not inevitable. Devices such as detectors are becoming widespread and can help reduce the risk of poisoning. In most cases, the safest method to avoid carbon monoxide poisoning is to install a CO detector. Just as a smoke detector will respond to a high level of CO2, a carbon monoxide detector will sound its alarm as soon as it detects a significant amount of carbon monoxide in the air.

In the UK, it’s mandatory to install a carbon monoxide detector in all homes that have fixed fuel-burning appliances. If you decide to install a detector in your house or apartment, you should ideally place a detector (or sensor) in each room where you have a heater (that uses any fuel other than electricity). This will help you to detect the gas at its source and sound an alarm before the first symptoms of carbon monoxide poisoning occur. Your detector must be mounted on a wall, at eye level, and between 1 and 3 metres from the device. Important note: this is a major difference from smoke detectors, which should be placed on the ceiling.

Prevention is better than treatment when it comes to carbon monoxide poisoning. There are several solutions to help you prevent poisoning from happening, so don't take any risks with your health at home!