The Lancashire Telegraph can reveal that a number of civil claims have been made against the force, and the suppliers of the equipment have since made changes to prevent ‘audio anomalies’.

The Constabulary has revealed it has already paid £20,000 to minimise the risk of future problems with the equipment.

The Airwave equipment is supplied via the Home Office contract held jointly by Motorola, which provides the handsets, and O2, which operates the mobile communications network aspect.

Lancashire was the first force to pilot the new Airwave communications technology and TETRA radios in 2001 and at the time, the federation’s local branch reported 176 users had reported sick with symptoms such as nausea, headaches and stomach pains which they blamed on the new equipment.

The Health and Safety Executive was called in but declared there was no link.

At a recent meeting of the Audit and Standards Committee, the authority presented its statement of accounts for 2008/09, which made reference to a ‘contingent liability in respect of Airwave liability claims’.

A spokesman for Lancashire Police Authority said: “The Authority has received a number of liability claims for injury allegedly resulting from the use of the Constabulary’s mobile communications equipment.

“This is an ongoing matter and the outcomes from the claims are not yet known.”

The Lancashire Telegraph put in a request under the Freedom of Information Act to find out how many officers are claiming to have been badly affected by the Airwave system, but most of its questions were refused due to ‘ongoing investigations’.

John O’Reilly, chairman of the Lancashire Police Federation, said: “When we first got it there were all sorts of problems, including breakdowns in communication and certain parts of the county being unreachable.

“But then most or all of the problems were ironed out over a period of time by improved technology.”