A NOXIOUS gas leak sparked the evacuation of a school during GCSE and A-Level exams. The fire brigade was called to Jo Richardson School, Gale Street, Dagenham, on June 11 (Thursday) at 3.04pm where a container of Calcium Chlorate had been leaking in a st

A NOXIOUS gas leak sparked the evacuation of a school during GCSE and A-Level exams.

The fire brigade was called to Jo Richardson School, Gale Street, Dagenham, on June 11 (Thursday) at 3.04pm where a container of Calcium Chlorate had been leaking in a storage room and led to the spread of chlorine gas.

Around 300grammes of the substance were thought to have been spilled.

Chlorine gas can be fatal if inhaled or ingested.

It is used in school experiments as part of the science curriculum.

Head teacher Ges Smith said: "The container disintegrated and broke during a stock take.

"The lab technician followed the procedure on a hazard card which said that you wash the chemical away."

The school decided to take some further advice and called the fire brigade at 3pm.

Crews from Dagenham, Barking and Wennington, and police officers, attended and blocked the road at the junction of Goresbrook Road and Gale Street.

Six fire engines, an ambulance and a scientific support unit were at the scene, where a decontamination tent was set up.

The school was evacuated but Mr Smith said it did not cause much disturbance as it happened at the end of the school day.

However, 70 students were sitting GCSE exams and two were sitting A-Level exams until 3.15pm, which meant that the fire alarm could not be used as it would have disturbed the exams.

Specially trained fire officers in chemical protective suits went into the storage room from an external entrance at the back of the school and removed the substance.

Mr Smith said: "When they went in they used meters and reading equipment but the readings were all neutral.

"Working in a school you get to be very, very careful."

The road was re-opened at 6pm and classes resumed as normal on the following day.