A science teacher sets a fireball off at a school in Sydney to warn others of the highly reactive replacement 'town gas' for helium in party balloons.

The teacher, Jacob Strickling, explains that "town gas is very reactive and ignites in a big orange fireball. This reactivity makes it very dangerous to breathe in," unlike the helium gas normally used to make voices go high pitched and squeaky.

The demonstration was shot on August 8.

Australian Science Teacher Jacob Strickling, also known as the ‘Nutty Professor’ demonstrates why it could be dangerous to breathe in the gas in party balloons. Helium, which is a lighter than air gas and also non reactive is safe to breathe in and will cause the voice to go high pitch and squeaky. However Helium is getting more expensive as it is a very limited resource. This means that some party balloon suppliers are instead using town gas which is also lighter than air to fill the party balloons. Town gas however is very reactive as shown in the video and ignites in a big orange fireball. This reactivity makes it very dangerous to breathe in. Strickling is the creator behind the YouTube Channel ‘Make Science Fun’ and is known for his hands on approach to Science.