Members of the emergency services are alarmed that television dramas are putting lives at risk by broadcasting misleading portrayals of their work.

A report by the Broadcasting Standards Commission, a government watchdog, has found that viewers are convinced of the accuracy of drama programmes, such as the BBC's popular Casualty series, and use them to make critical judgements.

The commission interviewed police and ambulance workers, as well as 2,000 members of the public. Ambulance workers said patients frequently complained that drivers were not using their blue emergency lights when taking them to hospital, because they said they were always used in television dramas.

Other workers complained that misleading advice in fictional programmes had put lives in danger. One ambulance worker told the commission: "This guy had obviously seen something on television or film, that you put something in [eplilepsy sufferers'] mouths to stop them biting their tongue. So he pulled out a 50p piece. Not only am I dealing with this guy fitting, he's now semi-choking on a 50p piece. It was just chaos."

Another viewer gave an emergency services worker unwanted instructions on how to perform throat surgery. The worker said: "[He] insisted he knew he could do a tracheotomy. He was like, 'No, you put it in the neck, then you make the incision, turn it 90 degrees. Get out a biro, I saw it on Casualty.'"

Other emergency staff complained that television made 999 workers look unprofessional. One worker said: "When the ambulance service is striving to look like a profession and you're getting these TV programmes which are totally undermining that, it's quite irritating."

Police also complained to the commission that people they arrested frequently complained that they were being denied a telephone call from the station, because they had seen it portrayed as their right on television.

Even the successes of television cops in tackling crime had a potentially damaging effect on police work, the report claimed. "The routine solving of crime in police drama was reported to have raised expectations among crime victims that their case would be similarly resolved," it said.

Paul Bolt, director of the BSC, said the survey showed that although viewers recognised television dramas as "fictitious representation" they expected programmes to be "factually accurate".

He said: "We look to drama for entertainment but it also helps to shape our view of the world we live in.

"People don't want or expect a faithful reflection of often humdrum reality - but they don't expect to be misled by distortions of the truth either."