Having faith in your workmen is all well and good, but sometimes it is misplaced, as Clare and Audrey found to their horror. Penny Jackson finds out why

Two weeks ago, Audrey Chaussin, working as an au pair in London, was lucky not to have been killed while taking a shower. As she stepped into a running bath she reached out for the shower attachment. At once her whole body started shaking. She managed to turn off the tap before dropping the shower and clambering out of the bath.

Since she was alone in the house her first thought was to call her mother in France. "I was very frightened. I thought I was ill," recalls Ms Chaussin. "But when I described to my mother what had happened she suggested that it could be an electric shock. The washing machine and dryer are both in the bathroom and it was the first time I had taken a shower while they were working."

By contrast, it was quite usual for her employer, Clare Wessely, to get up early and put on the washing machine before showering. "I had felt tingling on and off for a long time and it had got worse over the past few months. But nobody else felt it, so I put it down to static and assumed it was just me. As soon as Audrey told us what had happened we had everything checked. It is terrifying to think what might have happened," says Mrs Wessely.

The electrician who was called in discovered that the washing machine had not been earthed and was also on a single wire, not a ring main. "It was lethal," he says. "The electric current was being carried through the water pipes and it could easily have caused a fatal accident. The workmanship was terrible and the appliances should never have been put in the bathroom in the first place."

Even though it was only three years ago that the Wesselys had major work done on their London house, they now face another bill for its rewiring. The scenario is not unfamiliar. The building company, recommended by their architect, has since gone out of business.

"We realised right from the beginning that the electrician was a disaster. He put in a transformer the size of a house and successive electricians have commented that it should be in a museum", says Clare Wessely.

The family is by no means alone in finding that the person or company responsible for sub-standard work is no longer accountable. But, if someone is doing a job in a dangerous manner, it cannot be shrugged off. So where to start?

If an architect has been involved, it might be tempting to place the responsibility there. Tony Chapman of the Royal Institute of British Architects (RIBA), says that the architect does bear some responsibility if he signs work off. An architect must ensure that craftsmen he or she recommends or appoints are fully qualified and that certificates are issued as to the quality of the work. "This is in effect self-certification since architects cannot check every pipe or bit of wiring." Qualifications should guarantee a good standard of workmanship.

In the gas installing business Corgi registration has been tightened up. Last month an identity card scheme was launched so that at a glance customers can check the credentials and areas of competence of the operative. The nearest equivalent in the electrical world is the National Inspection Council for Electrical Installation contractors, (NICIEC) but unlike Corgi registration it is not required under law.

However, the NICIEC and the Institute of Electrical Engineers do provide some redress if one of their members is guilty of sub-standard work. Poor workmanship was used for the first time in a charge of manslaughter after a young father was killed by an electric shock from a sink when a central heating system was wrongly wired.

The electrician charged had connected the live pin in a central heating programmer to the earth in the junction box, which resulted in the radiators and pipework in the house being live. In another case, in which a teenager was electrocuted by a faulty power shower, it was not possible to trace the person responsible.

The evidence of negligence can sometimes take years to manifest itself and this can be a problem when it comes to providing evidence in the courts. But where a company or a person is clearly putting lives at risk, the Health and Safety Executive will make strenuous efforts to seek the offender.

"We might liaise with the local authority and the police and in the past have gone to great lengths to track people down", says Mark Wheeler of the HSE. "It is difficult to pursue when companies go out of business but individuals cannot change their status. The regulations covering electrical work are very specific. Where a professional job is being done, the home becomes the work place so that if a builder, say, is putting in a loft extension the house is in effect a construction site."

There is plenty of evidence that most people have great faith in the skill of others, especially in areas of which they themselves know little. But according to Clare Wessely's electrician, we should all be more cautious. "I have seen some terrible jobs. It is better to get it checked by someone else than live with doubts. It could have been much worse for the young French girl."