A group of Shropshire office workers who have spent three years trying to prove that faulty air conditioning left them with serious health problems have been told their case will go no further.

Eleven former British Telecom employees who worked on the fifth floor of the Telford Plaza 2 have been trying to bring legal action against BT with the help of the Communication Workers’ Union.

They claim bacteria from a poorly-maintained air conditioning unit left them with “sick building syndrome”.

Their symptoms included dizziness and nausea, chest infections, skin rashes, memory loss, slurred speech, eye problems and difficulty concentrating. Several underwent brain scans.

But they have been told by the CWU it cannot support their case, despite spending several thousand pounds on it since 2006. Steve Jesson, the solicitor acting on behalf of the workers, said there was not a strong enough chance of proving the symptoms were caused by faulty air conditioning.

In 2006 BT installed new air conditioning after moving out of the Plaza. It said the previous air conditioning was not suitable for the new occupants. The company said it could not comment on any potential or actual legal claim against it.

Unless a new solicitor can be found to continue the case by October, it will cease.

Chris Moss, of High Ercall, worked there between 2002 and 2004. She said: “We have wasted years after being told that we had a claim.”

Marilyn Davies, another claimant, said she was “gutted”. Mrs Davies, of Leegomery, carried on working for BT after the office moved to Shrewsbury, but she had a lot of time off sick and still has breathing problems.

In 2006 a report from forensic engineer Jerry Fagan, of Jacobs Babtie, said he had “never witnessed such extensive contamination” in an air conditioning unit.

The fifth floor of Telford Plaza 2 has been run as serviced offices by United Business Centres since May 2008. The firm said there had been no health problems.

A spokeswoman for the CWU said: “We have not given up on this case. If we can make the link between the building and the medical condition of the people involved we will then be in a position to consider making a claim against those responsible.”

By Andrew Owen