The Unite union is calling for a commitment to “World class safety” at the Ineos Grangemouth plant in Scotland after a gas leak caused a lock down of the oil refinery and chemical plant and the surrounding area.

Roads were closed around the Ineos site as the police and fire services responded to reports of a leak of butane gas at about 10:45am on Tuesday 30 September.

An Ineos spokesman confirmed the on-site incident management team was mobilised in response to the leak. No-one was injured and a police spokesman said there was no wider risk to people living nearby.

Hundreds of staff and pupils at nearby schools were advised to stay indoors as a precaution during the incident. Road closures were removed by noon.

Commenting on the leak , Pat Rafferty, Scottish secretary of the Unite, said: “Grangemouth is Scotland’s premier industrial site so it is vital that the workforce, the local community and the contractors can have every confidence that it is being run with maximum emphasis on safety.

“This leak is not a minor incident. The lock-down of the site and the surrounding areas, including the need for local schools to keep children indoors until the all-clear was given, was a reflection of the severity of this incident.

“Unite has stressed time and again that the best way to maintain the highest safety standards at the site is to work with the union and our expert safety reps. It is no secret to the company that we are seriously concerned that the number of safety specialists on the site has been cut to a level we regard as unacceptable and so I stress again to Ineos, work with us to rectify this situation.

“When we sit down with the Health and Safety Executive, as planned for later in October, we will also be looking for their commitment to delivering world class safety at the Grangemouth site. Scottish and UK taxpayers have invested in this plant; at the very least they must have confidence in its operations.”