Recently there have been many stories in the media regarding the use of gas stoves, heaters and lanterns inside a tent which have resulted in tragedy. Despite the dangers of carbon monoxide poisoning, using a stove inside an enclosed vestibule or tent is actually common practice amongst mountaineers especially if it’s blowing a blizzard outside. So for those campers who still wish to risk exposure to the deadly gas we’ve put together some common sense tips.

Carbon monoxide or CO is a deadly gas that is formed when a fuel burns in an enclosed space where little oxygen is available, for example inside a tent. The gas is colourless and odourless and can produce minor symptoms of headaches, sickness and fatigue whilst long term exposure can lead to death or brain damage.

A little bit of science

Usually we breathe in oxygen which temporarily binds to our red blood cells and this is then carried all around our body and eventually expelled again out of our lungs. If carbon monoxide is introduced it permanently attaches itself to the red blood cell, meaning that the oxygen is unable to catch a ride. This results in a lack of oxygen delivered to the whole body and can result in damage to brain tissues. This toxic gas takes up to 5 hours of normal breathing to eliminate just 50% of the carbon monoxide taken in. At higher altitudes it would take a lot longer to remove the build up of the toxin.

Symptoms of carbon monoxide poisoning

Watch out for any of these short term symptoms. If any of these are present it’s best to immediately turn off any appliances and move to a well ventilated area. Seek medical attention as soon as possible

• Headaches
• Nausea and vomiting
• Lethargy
• Dizziness
• A cherry red appearance to lips and skin
• Confusion and visual disturbance
• Loss of dexterity
• Rapid heartbeat

Longer term symptoms include the following

• Incontinence
• Collapse
• Seizures
• Coma
• Death

So how can you reduce your risk of carbon monoxide exposure?

• Increase ventilation to remove CO build up and allow oxygen to enter
• Choose a removable groundsheet tent where these is increase ventilation
• Prevent snow or ice from covering the fly sheet and regularly clean tent fabrics to ensure they remain porous
• Get up and take a walk in fresh air which might reveal any symptoms.
• A yellow sooty flame suggests CO is being formed due to a lack of oxygen so keep and eye on your appliance. It might need a clean, fuel replaced or setting at a higher output level. You want a blue, clean flame!
• Low outputs and flames for simmering will produce more CO.
• Some fuels are ‘dirty’ and will produce more of the toxin. Kerosene is dirty whereas gases such as propane and butane and methylated spirits are ‘clean’.
• Don’t agitate your flame! Placing a pot over the flame will increase CO production so consider a pot support or using a very small pot

At note about use at high altitude

The risk of CO poisoning at high altitudes is amplified in various ways.

Ice and snow on tents can trap the gas inside further and because the environment is cold you’re more likely to fire that stove up to keep warm.

At high altitude there is a decreased oxygen pressure meaning blood will already be holding little oxygen resulting in a faster breathing rate and increased fatigue from normal activities. Breathing faster would mean you would inhale more CO from that burning stove.

Being at high altitudes for longer periods causes the body to create more red blood cells just to cope with the lack of oxygen. This means there are more cells for the toxin to attach to. When you then move down to sea level your body would be bursting with the toxin and causes it to linger longer than usual.