---
title: What is CO?
description: What is Carbon Monoxide (CO)?
---

[Skip to content](https://support.bedfont.com/en/knowledge/what-is-co#main-content)

English

Show submenu for translations

[Customer portal](https://support.bedfont.com/ticket-portal?hsLang=en)

![Bedfont logo-high resolution png-2](https://support.bedfont.com/hs-fs/hubfs/Bedfont%20logo-high%20resolution%20png-2.webp?width=120&height=122&name=Bedfont%20logo-high%20resolution%20png-2.webp)

- [Raise a Support Ticket](https://ticket.bedfont.com/)

Open main navigation

Close main navigation

- [Raise a Support Ticket](https://ticket.bedfont.com/)
- English
  
  Show submenu for translations
- [Customer portal](https://support.bedfont.com/ticket-portal)
- Go to www.bedfont.com

 Go to www.bedfont.com

 Hello. How can we help you?

- There are no suggestions because the search field is empty.

1. [Help Centre](https://support.bedfont.com/en/knowledge?hsLang=en)
2. [Smokerlyzer](https://support.bedfont.com/en/knowledge/smokerlyzer?hsLang=en)
3. [FAQ](https://support.bedfont.com/en/knowledge/smokerlyzer?hsLang=en#faq)

# What is CO?

## What is Carbon Monoxide (CO)?

Carbon monoxide (CO), known as the silent killer, is a colourless, odourless, highly poisonous gas that is produced when fuels are burned incompletely. It is produced in car exhaust fumes, faulty gas boilers and tobacco smoke(1). When you inhale smoke from a cigarette, the CO is absorbed into your blood, forming %COHb, which prevents oxygen from being carried around your body to vital organs, resulting in many damaging health effects.

If the problem persists or has not been resolved by the information provided above, please contact your local distributor for more information. Find out who your local distributor is from our website [here](https://www.bedfont.com/find-my-distributor). 

**References**

1\. Andrew H. Carbon Monoxide ‘The Silent Killer’ Feasibility Study 2009/2010. 1st ed. London: London Ambulance; 2017

- [NObreath](https://support.bedfont.com/en/knowledge/nobreath?hsLang=en#main-content)

    - [FAQ](https://support.bedfont.com/en/knowledge/nobreath?hsLang=en#faq)
    - [On screen symbols](https://support.bedfont.com/en/knowledge/nobreath?hsLang=en#on-screen-symbols)
    - [Device function issues](https://support.bedfont.com/en/knowledge/nobreath?hsLang=en#device-function-issues)
    - [Infection control](https://support.bedfont.com/en/knowledge/nobreath?hsLang=en#infection-control)
    - [Safe Breath Testing During COVID-19](https://support.bedfont.com/en/knowledge/nobreath?hsLang=en#safe-breath-testing-during-covid-19)
    - [Firmware](https://support.bedfont.com/en/knowledge/nobreath?hsLang=en#firmware)
- [Smokerlyzer](https://support.bedfont.com/en/knowledge/smokerlyzer?hsLang=en#main-content)

    - [FAQ](https://support.bedfont.com/en/knowledge/smokerlyzer?hsLang=en#faq)
    - [On screen symbols](https://support.bedfont.com/en/knowledge/smokerlyzer?hsLang=en#on-screen-symbols)
    - [Device function issues](https://support.bedfont.com/en/knowledge/smokerlyzer?hsLang=en#device-function-issues)
    - [Maintenance](https://support.bedfont.com/en/knowledge/smokerlyzer?hsLang=en#maintenance)
    - [Infection control](https://support.bedfont.com/en/knowledge/smokerlyzer?hsLang=en#infection-control)
    - [Safe Breath Testing During COVID-19](https://support.bedfont.com/en/knowledge/smokerlyzer?hsLang=en#safe-breath-testing-during-covid-19)
    - [Firmware](https://support.bedfont.com/en/knowledge/smokerlyzer?hsLang=en#firmware)
- [Gastrolyzer](https://support.bedfont.com/en/knowledge/gastrolyzer?hsLang=en#main-content)

    - [FAQ](https://support.bedfont.com/en/knowledge/gastrolyzer?hsLang=en#faq)
    - [On screen symbols](https://support.bedfont.com/en/knowledge/gastrolyzer?hsLang=en#on-screen-symbols)
    - [Device function issues](https://support.bedfont.com/en/knowledge/gastrolyzer?hsLang=en#device-function-issues)
    - [Maintenance](https://support.bedfont.com/en/knowledge/gastrolyzer?hsLang=en#maintenance)
    - [Infection control](https://support.bedfont.com/en/knowledge/gastrolyzer?hsLang=en#infection-control)
    - [Firmware](https://support.bedfont.com/en/knowledge/gastrolyzer?hsLang=en#firmware)
- [Medi-Gas Check](https://support.bedfont.com/en/knowledge/medi-gas-check?hsLang=en#main-content)

    - [FAQ](https://support.bedfont.com/en/knowledge/medi-gas-check?hsLang=en#faq)
- [ToxCO](https://support.bedfont.com/en/knowledge/toxco?hsLang=en#main-content)

    - [On screen symbols](https://support.bedfont.com/en/knowledge/toxco?hsLang=en#on-screen-symbols)
    - [Device function issues](https://support.bedfont.com/en/knowledge/toxco?hsLang=en#device-function-issues)
    - [Maintenance](https://support.bedfont.com/en/knowledge/toxco?hsLang=en#maintenance)
    - [Infection control](https://support.bedfont.com/en/knowledge/toxco?hsLang=en#infection-control)
- [FAQ](https://support.bedfont.com/en/knowledge/faq?hsLang=en)

[![Bedfont logo-high resolution png-2-1](https://support.bedfont.com/hs-fs/hubfs/Bedfont%20logo-high%20resolution%20png-2-1.webp?width=120&height=122&name=Bedfont%20logo-high%20resolution%20png-2-1.webp "Bedfont logo-high resolution png-2-1")](http://www.bedfont.com)

Bedfont Scientific Ltd - Help Center

Copyright © 2026, Bedfont Scientific Ltd.