Just under half of workplaces in the UK have never been visited by a health and safety inspector, according to the Trades Union Congress (TUC).

This is despite evidence that inspection and enforcement activity is the most effective way to ensure that employers comply with health and safety laws.

In small companies who employ less than 50 people only 16% have had an inspection in the last year. Even among large workplaces with over 1,000 workers, only one third have been inspected within the last 12 months.

"It is a scandal that nearly half of workplaces in the UK have never been visited by a health and safety inspector," said TUC General Secretary Brendan Barber.

"More than a million workers are currently suffering from an illness or injury caused by their work, and in 2009 over 30 million days were lost due to work-related sickness absence. This time off work cost employers £3.7bn - yet much of this could have been prevented if they had ensured their workplaces were safe."