As part of our commitment to sharing our knowledge and expertise of gas detection safety around the world, we have created a series of short and to-the-point “factoid” videos, covering a variety of gas-related hazards. As with all our videos, they are intended to be watched, downloaded and/or shared however helps you. Please use them to spread the word and improve gas detection safety.
This first video focuses on risks associated with either too little or too much oxygen (O2).
Oxygen – the Goldilocks of gases
Oxygen, normally present in air at 20.9%, is essential to most life. The majority of people recognise that insufficient O2 is not healthy, but fewer may be aware that too much is also dangerous. The levels of this gas need to be just right.
Hypoxia from insufficient O2
It is generally recognised that O2 levels below 19.5% are dangerous, and can lead to hypoxia; severe symptoms of this can include confusion, disorientation, hallucinations, behavioural change, severe headaches and reduced level of consciousness. Oxygen levels can be lowered by displacement by other gases. It is also “consumed” by the chemical reactions that occur when fuels burn, metals rust and vegetation rots.
Hyperoxia from too much O2
Too much oxygen in the air can also be highly dangerous if care is not taken. This can be caused by O2 leaking into the general environment around processes which use oxygen; from welding and flame cutting, to food preservation and packaging; from steelworks to chemical plants; and across a variety of medical applications. Extended exposure to elevated oxygen levels can result in hyperoxia. Symptoms may include disorientation, breathing problems, and vision changes.
An increase in O2 levels to just 24% significantly increases fire-related risk, too. Not only do things ignite more easily, but they can burn hotter and more fiercely. Extinguishing a flame could become almost impossible. Under pressure, pure oxygen can react violently with materials such as oil and grease which would normally be quite unreactive. Many materials used routinely in other circumstances are incompatible with use in oxygen-rich environments, as they may spontaneously catch fire or react explosively.
What should you do if you suspect oxygen enrichment?
– Turn off the oxygen supply
– Extinguish cigarettes and open flames
– Ensure the room is well ventilated
– Identify and repair the source
Oxygen use in the work place – Fire and Explosion Hazards is a useful guide for anyone working with oxygen cylinders. Published by the UK Health & Safety Executive (HSE), it highlights good standards, enabling companies around the world to conform to best practice. Download a free PDF from the UK government’s HSE website.
Find out more about Oxygen Risks here