The Health and Safety Executive (HSE) has warned schools that they must put appropriate safety measures in place following an incident in which a 16-year-old girl suffered burns so serious that she had to have most of her fingers amputated.

During an A Level art class at the Giles School in Lincolnshire, the unnamed girl decided to make a plaster cast of her hands and filled a vat with plaster of Paris.

However, she was unaware that the substance gives off intense heat when mixed with water – an exothermic reaction – and she plunged her hands into it. The plaster set rapidly and the pupil was unable to get her hands out. Staff and fellow students tried, but an ambulance had to be called while the girl’s hands were burning inside the plaster.

After she got to hospital, it was found that her injuries were so severe that she had to have both of her thumbs and all but two of her fingers amputated.

The school’s governing body was fined for breaching health and safety regulations, and HSE inspector Jo Anderson said the incident should serve as a warning after it was found that pupils were not instructed about the dangers plaster of Paris could pose.

"We want the public to understand that risk assessments in educational establishments must not be viewed as burdensome, but instead, paramount to pupil safety," she remarked.