THE Health and Safety Executive has launched an investigation after the second chemical spill at a Gwent factory.

As we reported on this website yesterday, 11 workers were given precautionary hospital treatment and covered in an antidote gel after potentially being exposed to the spilt hydrofluoric acid at Doncasters, Blaenavon.

Now the Health and Safety Executive has been called in to investigate the incident at the plant on Gilchrist Thomas Industrial Estate.

They have asked the company to provide a full incident report and say their investigation is underway.

Hydrofluoric acid is extremely dangerous, but symptoms do not always show up immediately, which can delay treatment, which is why workers were taken into hospital as a precaution.

Calcium gluconate gel is often applied as a preventative antidote if there is any risk the patient's skin has come into contact with hydrofluoric acid.

The acid has a boiling point of just 19.5 degrees, so there is also a strong risk of inhalation where spillages.

The firm said its emergency team and staff worked closely with the fire service, Torfaen council and the Environment Agency to assess and "immediately" contain the spill that happened at 12.30pm on Tuesday.

Firefighters from Brynmawr, Ebbw Vale, Blaina, and Cwmbran, wearing protective suits cordoned off the area until it was made safe by 3pm.

A similar incident occurred two years ago at the plant, which manufactures engine blade components for the aircraft, automotive and power industries.

The Welsh Ambulance Service confirmed 11 people were taken to hospital following the incident.

They have since been discharged.

Although no contamination was detected it is understood precautionary treatment of an antidote gel was administered, as is standard for incidents involving hydrofluoric acid.

A Gwent NHS Healthcare Trust spokesman said: "Patients were brought into the Royal Gwent Hospital and Nevill Hall Hospital from this incident. As no contamination was detected they were discharged and given instructions for observation.

"Our usual procedures for dealing with a chemical incident were put in place to protect for the safety of other patients and our staff."

Doncasters were unavailable for comment.