Argon is a common, inert gas that makes up about 1% of the earth’s atmosphere. It is colorless and odorless. Argon is used widely in the welding industry as a ‘shield gas’ and can be purchased in take-home cylinders.
Helium
Helium is an inert gas, that is colorless and odorless and much lighter than air. It cannot be manufactured and global supplies are limited. Helium has many industrial applications yet its dwindling supply means that the price of the gas is rising. Take-home cylinders of ‘Balloon Time’ pure helium (for party balloon inflation) are no longer available.
A Short History of Helium & Balloon Time Cylinders
For many years, Balloon Time cylinders (from Worthington, Ohio, US) were a cheap, disposable source of helium gas. The balloon kits were sold online from stores such as Amazon, Argos, Tescos and Spotlight.
In 2015, Worthingtons announced that the gas in their disposable helium cylinders could be adulterated with to 20% air (ie. up to 4% oxygen). While this mixed gas still enables balloons to float, it is unsuitable to use for a hypoxic death.
Note: While compressed helium cylinders can be easily hired from gas suppliers such as BOC for the inflation of balloons for parties, home purchase is generally unavailable.