STUDENTS are at risk of inhaling potentially harmful gases in a school building which could catch fire, according to emails seen by the Comet.

Marriotts Lonsdale School in Stevenage opened its doors to students for the first time three weeks ago and has been declared as one of the best school buildings in the country by its headteachers.

But an engineer who worked for building contractors Balfour Beatty during the project has hit out at the company for not finishing the job.

Flue piping on the site in Brittain Way used to transfer gases, including sulphur and carbon monoxide, from four boilers inside the school to the outside are 1.28 metres short of the required height.

An email from design consultants AECOM sent to Balfour Beatty mechanical engineer Geraint Hughes in December said: “I believe all four flues should be increased to the necessary height.

“This is likely to be more of an issue when the biomass boilers are running due to the smoke produced and the likelihood of fumes being brought into the building via the air handling units and other openings.

“Also, there could be a risk of the building roof catching fire and so the height should be increased as per my previous comments on the flue drawing.”

Mr Hughes, who has since been made redundant by Balfour Beatty, told the Comet: “The pupils are being potentially poisoned by toxic flue gases as the contractors Balfour Beatty have constructed the flues too low.

“The consultants AECOM informed Balfour Beatty of this problem in March 2012 and they still haven’t fixed it.

“Balfour Beatty has handed the building over with the flues at the lower level, because they haven’t rectified the problem and didn’t want to tell the school the building wasn’t ready. It’s disgraceful.”

A spokesman for Balfour Beatty said: “We identified an issue with the biomass boiler flue height at the Marriotts Lonsdale School in late November 2012. The issue was immediately investigated with our consulting engineers AECOM and a plan for addressing the issue was put in place.

“The flue height is not a health and safety issue which would prevent the school from opening and our plan and timing for addressing the issue received approval from the independent certifier, Stevenage Borough Council’s building control department. Works to amend the height of the flue will be completed by the end of February 2013 as planned.”

A spokesman for Hertfordshire County Council, which oversaw the build, said the work was a “building performance issue rather than a health and safety risk” and as such will be carried out after the school breaks up for half term on February 15.

For an interview with the Marriotts and Lonsdale headteachers keep checking our website.