Lancashire constabulary, which begins piloting the scheme from the end of February, said fears over interference from the handsets prompted the move. There are also concerns that breath-test and speed-trap equipment could be affected.
The decision left the Police Federation worried. Federation chairman Fred Broughton said, "We are concerned that operational effectiveness will be hampered by the equipment and police officer safety compromised. We are seeking urgent talks with the Home Office and police chiefs to discuss the matter."
David Brindle, Lancashire project director, said, "There is a risk of interference but we don't know how much yet. We wish that we didn't have to do this but we are prepared to work around it because the benefits of the project, such as encryption and vastly improved coverage, are tremendous."
Like mobile phones, the radios transmit a regular pulse to base stations, which has the potential to cause interference.
Brindle said the Home Office is working to resolve the situation. He said, "The problem is that, because the level of pulse varies, it is difficult to gauge the actual level of impact."
Lancashire constabulary is preparing to test the equipment at Preston Royal Hospital to assess its impact on medical equipment.
Lancashire is the first UK constabulary to use the new digital handsets. Brindle said, "From the end of February the first of our six divisions, Preston Central, will use the radios. They will then be rolled out, on a month-by-month basis, to the other divisions."
Airwaves, the Public Safety Radio Communications Project, is supplied by BT, Motorola and TRW and should be rolled out to all 52 police forces by 2005.