CREWS are continuing to monitor levels of gas following a large fire at a chemical storage building in Cheshire.

At its height, six fire engines from Warrington, Lymm, Chester, Northwich and Tarporley fire stations attended the incident on Percival Lane, Runcorn, at about 7.45pm on Friday.

The blaze occurred a week after the same road saw a huge fire break out at a pallet yard, with plumes of smoke being seen for miles around.

On arrival at the scene on Friday, crews found a fire smouldering in the roof space of the unit where maintenance work had been carried out.

Additional fire engines were deployed to the scene owing to the fire producing hydrogen sulphide gas.

Firefighters wearing protective kit attempted to tackle the fire using the site’s own fire suppression system.

Gas monitors were also utilised, while crews were advised by a hazardous materials expert.

By 10.45pm, the incident had been scaled back to three fire engines, with firefighters continuing to monitor the scene while the ‘drencher’ system within the unit took effect.

As of midday on Saturday, employees in an adjacent site were asked to leave and nearby roads were closed as a precaution due to fears over escaped gas.

Firefighters remained at the scene to regularly take temperature checks of the silo and monitor gas levels.

Gas was said to be ‘well within safe limits’ by Saturday night, with the drencher system running in the silo through much of the day yesterday, Sunday.

An update issued last night revealed that gas levels around the silo were at zero, with site personnel monitoring the situation overnight.

Fire crews returned this morning, Monday, to conduct a thorough assessment of the silo, where very low readings of gas could be detected only in very close proximity to a vent.

A very small amount of steam is still issuing from the silo, with firefighters due to return at 5pm to make another assessment.