Why are carbon monoxide detectors important? A complete guide

Carbon monoxide is known as a ‘silent killer’, due to the fact it goes undetected to our senses - it doesn’t smell of anything and it has no colour. This dangerous gas is released by fuel burning and gas appliances in environments with low levels of oxygen, like boilers. 

Here, in this BOXT guide, we explore everything you need to know about carbon monoxide (CO). Our gas boiler experts will share their knowledge on the dangers of carbon monoxide poisoning, the different types of carbon monoxide alarms, and more, to help you and your family stay safe at home.

What is carbon monoxide?

Carbon monoxide is a poisonous and flammable gas, as well as colourless, odourless and tasteless. This combination makes it very dangerous and very difficult to detect carbon monoxide leaks. 

In fact, the only real way to identify that there is an issue is through a carbon monoxide alarm or tester (sometimes called a CO detector after the chemical formula). Luckily, these are readily available in most high street hardware stores and online, so you won’t struggle to get hold of one if your home doesn’t already have one installed.  

In terms of your boiler, carbon monoxide can be produced if an appliance is faulty or potentially if the flue is blocked. Other fuel burning appliances that may give off carbon monoxide include fireplaces with wood burners, water heaters, BBQs, and ovens. 

What are the dangers of carbon monoxide?

Carbon monoxide can be fatal, especially if inhaled in high doses - this is known as carbon monoxide poisoning. 

The symptoms of carbon monoxide poisoning include: 

• Feeling dizzy, disoriented or sick
• Shortness of breath
• Stomach pains

As well as being difficult to notice carbon monoxide leaks, carbon monoxide poisoning can be difficult to diagnose, too. The reason for this is twofold; firstly because, once you’re out of the gas-infected environment, the symptoms can clear, and secondly because the symptoms themselves can often be mistaken for other illnesses such as flu and food poisoning. 

This combination of being difficult to detect and easy to misdiagnose is what gives carbon monoxide its title of the silent killer, since victims don’t usually realise they’re in danger until it’s too late.   

When carbon monoxide is breathed in, it enters your bloodstream, mixing with haemoglobin, the red blood cells which carry oxygen around the body. When both of these things mix together, the blood can no longer carry oxygen. As a result, the body’s cells and tissue begin to fail.

Where can carbon monoxide be produced?

Carbon monoxide can be generated in many different locations around our homes and, perhaps even more worryingly, by appliances that we may use every single day. Below, we’ve listed some of the main offenders to be aware of.

• Blocked or poorly fitted boiler flues and chimneys
• Portable heaters that use liquid gas
• Gas appliances, like boilers, ovens and fires
• Vehicle exhausts/engines
• Charcoal and gas BBQs

Do you need a carbon monoxide detector?

In short, yes. As stated on the Gov.UK website and Government Building Regulations, “A carbon monoxide alarm should be installed in every room which is used as living accommodation containing a fixed combustion appliance (excluding gas cookers).” These regulations were updated in October 2022 to say an alarm should be provided “where a new or replacement fixed solid fuel appliance is installed in a dwelling.”

BOXT includes a carbon monoxide alarm as standard with every boiler installation to ensure your safety. 

Due to the number of fatal and non-fatal incidents caused by carbon monoxide poisoning,  it’s imperative that you have a carbon monoxide detector and alarm in your home, to give you peace of mind that your boiler and other appliances are working properly and not posing a silent threat to your family. 

What are the different types of carbon monoxide testers?

The easiest and quickest way to test for carbon monoxide gas is by using a carbon monoxide tester or detector. There are three main types of sensor on the different carbon monoxide detectors:

1. Biomimetic sensor – this sensor has a colour-changing pad or gel. When it detects carbon monoxide in the air - the colour will change and trigger an alarm.
2. Metal oxide sensor – when the chip in this detector senses the carbon monoxide gas, it will lower the electrical resistance and trigger the alarm.
3. Electrochemical sensor – in this sensor, electrodes inside a chemical solution can sense when they come into contact with the gas, which then triggers the alarm.

The cost of a carbon monoxide detector can vary, but they are usually relatively inexpensive. The higher-end detectors can cost around £25. Although more budget-friendly devices will be available, it is best to buy from a credible supplier. Considering the peace of mind you get with a carbon monoxide alarm, they offer exceptional value for money. 

A carbon monoxide detector should be installed alongside every new boiler installation. If not, the installer will be in breach of Government Building Regulations. With a boiler installation from BOXT, we take care of all of this for complete peace of mind.

If you're a fan of smart technology, the Google Nest Protect has been designed to detect any carbon monoxide as well as it being a smart smoke alarm.

How to use a carbon monoxide alarm

It’s crucial that you have a CO alarm installed in every room that contains a fuel-burning appliance, including near your boiler. You must also ensure you can hear the alarm throughout your home like you would a fire alarm. 

When you buy a CO detector, you should make sure you buy a certified product from a reputable DIY shop. Certified products will need to comply with the British standard EN505291 standard or a European approval mark. If you’re buying one for a houseboat or caravan, the carbon monoxide alarm will need to adhere to BS EN50291-2.

In terms of fitting CO detectors, you must follow the manufacturer’s instructions relating to where and how to fit the alarm. If you don’t feel confident doing this, you should seek help from a Gas Safe registered engineer.  

What does a carbon monoxide check involve?

As part of your annual boiler service, the engineer will ensure that there are no carbon monoxide leaks on the appliance. This is one of the reasons why having your boiler service annually is so important. More specifically, the boiler’s flue and pipework will be assessed, as well as the gas pressure. Once these checks are completed, the engineer will also ensure there are no gas leaks.

To ensure the safety of you and your family, book an annual boiler service today. Or, for more advice, get in touch with a Gas Safe registered engineer.