Hydrochloric acid, which is normally used to remove rust from iron, caused a chemical reaction with the magnesium alloy that produced hydrogen gas. The chemical reaction also produced hydrochloric acid fumes and caused the bath to become hot. The fumes prevented workers removing the crank case covers from the bath and the building was evacuated. The fire brigade neutralised the acid bath and removed the crank case covers. Fortunately no one was injured in the incident.
Hydrochloric fumes are an irritant and can cause tissue damage.
Hydrogen gas is highly flammable. The trades assistant did not have adequate training, instruction and supervision. He was told not to put magnesium alloy parts into the hydrochloric acid bath, but was not instructed of the consequences and emergency procedures. Employers must ensure that safe use, handling, processing, storage, transportation and disposal of substances in the workplace so that employees are not exposed to hazards. Employers must provide information, instruction, training and supervision so that employees can perform their work so they are not exposed to hazards.