Well that didn’t go according to plan. A group of students at a high school in Australia are now being treated at hospital for non-life threatening afflictions after a chemistry experiment went awry. The chemical contamination is so severe that it has been reported by News.com.au that HAZMAT teams were sent speeding in to deal with the mess.

Students at Concord High School in New South Wales were suffering from dizziness and minor respiratory difficulties on the morning of November 21 after an experiment that used a fume cupboard seemed to go wrong. Fume cupboards are used to suck out noxious or corrosive gases that emerge from specific chemical reactions, so whatever leaked out was certainly unfriendly.

Weirdly, although it was senior students conducting the experiment, it appears that the students that were affected belonged to a separate, younger year, and were located in another classroom. Several were treated at the scene for “chemical exposure”, and one was taken to Westmead Children’s Hospital for further assessment.

“We have up to seven children who are unwell,” a hospital spokesman said. “They are feeling light-headed and [are experiencing some] dizziness, but we don’t expect that it is serious.”

Although it can’t yet be confirmed what substance was unleashed, HAZMAT testing revealed elevated concentrations of carbon monoxide in the air near the school. Shortly after the team arrived, they managed to contain the fumes within the cupboard and the building had been properly ventilated.

Carbon monoxide, an odorless gas that can cause respiratory failure if inhaled in significant quantities, is normally released in incomplete combustion reactions.

If you’re burning methane, for example, you would normally get water and carbon dioxide if the environment was appropriately oxygenated. Incomplete combustion occurs when there’s a lack of oxygen, and it produces carbon monoxide too.

This is likely what led to the incident, although it’s rare for such things to go so badly under such carefully controlled conditions. It’s also extremely unclear how the students conducting the experiment were not affected, but those in another classroom were. Perhaps the filtration system had malfunctioned.

Either way, it’s good to know everyone will be fine – but please do be careful when conducting dangerous experiments at school!