Small and medium-sized businesses in Ireland spend more than €1.5 billion a year to counter the effects of theft and criminal activity, a new survey has found.

The survey of 400 businesses was carried out by the Irish Small and Medium Enterprises' Association (Isme).

It found that the average cost to businesses affected by crime was €4,200 per business or €446 million in total.

When security products such as CCTVs, alarms and manned security are included, the total cost rises to €1.5 billion annually.

The construction and retail sectors are the worst affected, according to the survey. Two-thirds of construction companies surveyed said they had been affected by crime, while 61 per cent of retailers were affected.

Theft by outsiders, burglary and damage to vehicles were the most common crimes experienced by companies.

Theft by staff members was also significant, with 14 per cent of those polled saying they had been affected by this.

The survey also found that only 7 per cent of criminals are apprehended for their crimes.

Just 3 per cent of those polled said they had confidence in the judicial system to prevent repeat criminal activity.

Nearly half the businesses polled said they had been affected by crime in the past 12 months.

The highest incidence of crime was in Co Dublin, at 57.9 per cent, and in Dublin city, at 56.2 per cent.

On a provincial basis, Connacht was the worst affected area with a 50 per cent rate, while Munster was least affected with a rate of 26.5 per cent.

To counter the problem, Isme has recommended the establishment of a national forum on crime, with a mandate to investigate the extent of crime and its impact on businesses.

It also called for an increase in the number of gardaí, more CCTVs in town centres and a greater emphasis on "business watch" initiatives.