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Due to current circumstances regarding the COVID-19 virus, we are currently operating a limited service and response times are longer than normal.

All of our services and latest information are available on our website using the main navigation or found on our dedicated COVID-19 FAQ page. If you can’t find the information you need, the fastest way to get hold of us is to email us at register@GasSafeRegister.co.uk. For consumers who are unable to use our website, the Gas Safety Advice line is available 9am-5pm on 0800 300 363 where we will aim to respond to you as soon as we are able.

What is carbon monoxide (CO)?

Carbon monoxide (CO) is a highly poisonous gas produced by the incomplete burning of natural gas or liquefied petroleum gas (LPG). This can happen when a gas appliance has been incorrectly fitted, badly repaired or poorly maintained. It can also occur if flues, chimneys or vents are blocked. Solid fuels, such as coal, wood, petrol, as well as oil, can also produce carbon monoxide when they burn.

CO can be deadly and is especially dangerous because you can’t see, taste or smell it, and some symptoms mimic the effects of viruses and even a bad hangover. It’s important to know the physical symptoms of CO poisoning to ensure you seek help quickly.

What are the physical symptoms of CO poisoning?

CO poisoning occurs when you breathe in CO and it replaces the oxygen in your bloodstream, causing body tissue and cells to die. Even small amounts of the gas can cause poisoning, and long term exposure can result in paralysis and even brain damage.

CO poisoning symptoms are similar to those of flu, food poisoning, viral infections, fatigue, and a hangover which makes it easy to mistake this very dangerous poisoning for something else.

The six main symptoms to look out for are:

  1. Headaches
  2. Dizziness
  3. Nausea
  4. Breathlessness
  5. Collapse
  6. Loss of consciousness

Anybody who has overdone it on a night out will be familiar with some or all of those symptoms, but if you experience them without drinking it’s time to be concerned. Being aware of these symptoms could save your life.

There are also other signs that could indicate CO poisoning, such as:

  • Symptoms occur when you are at home but seem to disappear when you leave.
  • Others in your household (including pets) are experiencing similar symptoms at a similar time.

It’s important to know the signs of a carbon monoxide leak in your home, because knowing the signs can ensure you aren’t exposed to dangerous levels of CO for an extended period of time.

What are the signs of a carbon monoxide leak?

Any of the following could be a sign of CO in your home:

  • Floppy yellow or orange flame on your gas hob, rather than crisp blue
  • Dark, sooty staining on or around gas appliances
  • Pilot lights that frequently blow out
  • Increased condensation inside windows

If you detect any of these signs, please contact your Gas Safe registered engineer immediately to come and inspect your gas appliances and flues.

To find engineers who are qualified to investigate the presence of CO, go to the Check The Register page on this site, and follow these steps:

  1. Enter your postcode
  2. Under the ‘Select appliance type’ tab choose ‘Fumes Investigation’
  3. Click ‘Find’ to see the updated results.

Remember that not getting your gas appliances regularly checked, or using an engineer that isn’t Gas Safe registered, can put you and your family at risk.

Due to the ongoing COVID-19 situation, some engineers have had their qualifications temporarily extended whilst lockdown and social distancing measures are in place. To avoid any confusion, please use the ‘Check A Business’ function to ensure the business and engineer you’re employing is qualified and registered.

What to do if you suspect CO poisoning

  • Don’t delay - get fresh air immediately.
  • Open doors and windows, turn off gas appliances and leave the house.
  • See your doctor immediately or go to hospital. They can do a blood or breath test to check and can advise if you need treatment for CO poisoning.
  • If you think there is an immediate danger, call the Gas Emergency Helpline on 0800 111 999 (GB) or the relevant service for your area.

You can also visit the NHS website for detailed information on the symptoms of CO poisoning, what action to take and the treatment that’s usually provided.

Stay safe with a carbon monoxide alarm

The most important thing you can do to minimise the risk of CO is to ensure that your gas appliances are safety checked annually by a Gas Safe registered engineer.

Installing an accredited carbon monoxide leak detector, or audible CO alarm, in your home or business is a good second line of defence, as they emit a sound when CO is detected. However, because an alarm only activates once there is CO present, you should never rely on them as your sole form of prevention.

To ensure their effectiveness, make sure any alarm you buy is marked EN 50291 and has the British Standards Kitemark. We don’t recommend the use of ‘black spot detector’ warning strips because their warning is too easily missed and they don’t emit a sound, so they won’t alert you if you have a CO leak whilst you’re asleep.

What are carbon monoxide alarms?

Carbon monoxide detectors are an early alert for possible carbon monoxide poisoning. They can be installed in and around your home, as described in the manufacturer guidelines and work much like your fire or smoke alarm by sounding an alarm when they detect carbon monoxide. There are a variety of models available on the market so be sure to find one that will be suitable.

Modern CO alarms look like smoke alarms (which do not detect CO) and you can purchase one from around £20 at most major retail outlets, including DIY stores and supermarkets. It’s advisable to fit an alarm in every room with a gas appliance, following the manufacturer’s fitting instructions carefully. Typically, CO alarms have a lifetime of between 5-10 years. Just like your smoke alarm, remember to test your CO alarm regularly.

If you’re unsure which alarm to get, you can ask a Gas Safe registered engineer for advice.

Been affected?

If you have been affected by CO and would like to share your story please get in touch with us by email.