Ten hospitals are piloting a 'smart card' that would allow NHS employers to check the complete occupational health history and any police record of potential employees.

The card has been endorsed by the NHS Executive and the British Medical Association's junior doctors committee, and could tackle the problem of medical staff passing on potentially fatal diseases to patients.

Ministers are already under pressure to publish new guidelines on hepatitis B-infected medical staff. Six patients have died after contracting the disease from doctors since guidelines were issued in 1993.

Dr Stuart Miller, director of occupational medicine at Hammersmith Hospital, has been working on the smart card for 10 years. It carries a colour photograph, the holder's name and their medical or nursing registration personal identification number.

A microchip in the card contains standard occupational health information on diseases, including hepatitis B, and clearance for unsupervised access to children - in line with the recommendations of the Clothier report into the murder of four children by nurse Beverly Allitt.

National Business Systems has been developing the idea in partnership with Hammersmith Hospital for the past three years.

A complete system would cost around£6,000, but trusts could update conventional computer systems and photo-ID hardware for about£1,500.