NIGHTS will be less alarming for people living near car parks if the Environmental Protection Department has its way. It wants to limit the length of time car burglar alarms can legally sound. The department proposes to make it an offence to have an alarm that lasts more than five minutes, a move which would ensure more restful nights for people plagued by persistent alarms. And once an alarm is off, the department wants it to stay off until re-connected by the car owner. Systems which switch alarms back on automatically would be prohibited. Penalties have not yet been fixed, but the department hoped they would apply to both and existing alarms. A bill is to go before the Legislative Council by the end of the year, and the automotive and insurance industries have welcomed the controls. Kendy Chan Kin-chung, of the Hong Kong Automobile Association, said professional thieves could always find a way around alarms and the systems were not much of a deterrent. ''Those alarms annoy a lot of people, especially in the middle of the night, and cause a lot of nuisance. We don't have a problem with controlling them,'' he said. Mike Rushworth of the Motor Traders' Association said alarm systems that went off at the slightest provocation were being replaced by ones that flashed lights and had special codes to shut down the car if it was tampered with. Accident Insurers' Association manager Choy Kam-sing said the measures would not affect insurance policies. Assistant Director of Environmental Protection Fred Tromp said they decided to act after noticing complaints about the problem in the media, although few people had contacted the department's hotline. ''We recognise this is a problem and something we can do without,'' Mr Tromp said. He said the legislation would apply only to alarms that went off for more than five minutes, so properly operating alarms that did not go off at whim could stay. All new cars, taxis, vans and buses with front middle seats should have lap belts, and passengers should be forced to wear them, the influential Transport Advisory Committee recommended yesterday. The law is expected to be changed this year, when the use of back-seat belts will also become compulsory. But there are no plans to force vehicles to fit lap belts for the middle of the rear seat, or rear seat child restraints, committee chairman Professor Leung Chi-keung said.