Last week marked the 150th year since helium was discovered during a solar eclipse, by the French scientist Jules Janssen. If this conjures up images of party balloons and seeing who’s high pitched voice can sound the funniest*, you wouldn’t be wrong, but helium is also an integral element within many other different applications.
Helium (He) is one of the most lightest, non-flammable, noble gases and has no smell, taste or colour. The boiling point of helium is closer to zero, which means in its liquid form it can provide the lowest operating temperature of refrigerants. It can therefore be used in the MRI process as a magnet coolant.
Used in this form, helium can also cool down superconducting magnets which is required to increase efficiency of operation. Some of the most critical uses of helium is when it is combined with oxygen for the medical and laboratory industries for the treatment of illnesses such as asthma, emphysema and other respiratory problems. The combination can be absorbed into the lungs much quicker than exposure to oxygen only treatment.
In gas form, helium is also used as an inert shield for arc welding because it is non-reactive and allows for consistent weld at a higher heat transfer, helping to impact a higher work speed. Helium is often blended with argon, depending on the hat and shape of the weld, but pure helium is often used for seam welding.
The gas become relied upon in highlighting the source of leaks as it can be absorbed through solids three times quicker than air. Most commonly used in detecting leaks in the hulls of ships, high-pressure equipment like vacuums and cryogenic systems but also air conditioning systems in cars.
Helium is used as an inert gas combined with oxygen to create a safe breathing atmosphere for deep sea divers, ensuring they’re not exposed to high levels of nitrogen increasing the possibility ‘nitrogen narcosis’.
From the depths of the sea to outer space, helium is also needed to clean the fuel tanks on shuttles, once they’ve been emptied. Having properties of an inert gas means it will not react with any oxygen left in the tank and importantly, will not cause the pipes to freeze.
Highlighted above are some of the applications which rely on helium to function and operate, however it’s also important to remember that although safe to use in regulated quantities, an inert gas can also decrease oxygen levels to harmful levels extremely quickly.
Properties of inert gases means they won’t react with oxygen, but they displace it in the atmosphere instead. If the oxygen levels in a room drop by as little as 1.5% it can start to have effects on the human body.
Analox recommends that a full risk assessment is carried out where helium is being used, stored, or piped in order to assess the risk of asphyxiation.
A simple oxygen depletion monitor could save money, downtime and more importantly someone’s life.
We wish helium a very happy and ‘noble’ 150th birthday as it has become one of the most used and useful gases across a wide range of applications, and don’t worry, even if it blew out that many candles, we wouldn’t go up in flames!
*Please be advised that inhaling helium, even from a party balloon is extremely dangerous and can be fatal. Analox strongly advise against this.
MRI image- Photo by Ken Treloar on Unsplash