LONDON (AP) _ Some private security guards hired to protect British military bases have criminal records, are afraid of the dark or fall asleep on the job because of overwork, according to a parliamentary committee report.

Some guards have even smashed windows at the bases they were hired to protect, the House of Commons committee said.

The report, issued late Tuesday, was based on an inquiry into security at the bases following a series of terrorist attacks, including the bombing of the Royal Marine Music School in September. The bombing, claimed by the Irish Republican Army, killed 11 people.

There was a public outcry at the time when it was disclosed that private guards had partial responsibility for security at the school. Nearby residents said security had been lax.

The report by the parliamentary select committee on defense found the standards applied to private security guards hired by the Ministry of Defense were far lower than those applied to the military.

One committee member, Bruce George of the opposition Labor Party, called their training ''abysmally inadequate.''

As a result, the firms offer ''a consistently unsatisfactory and potentially dangerous'' level of service, the report said.

Allan Rogers, Labor's spokesman on defense, said the report ''is a fairly savage indictment of the government and of the whole process of security.''

He called for government regulation of the private security industry.

Of the 2,000 or so military facilities in Britain, 56 use private security companies. A spokesman for the defense ministry said security guards are used for low-level tasks to free trained military personnel for more important work.

Rogers said the firms are hired because it is cheaper to use private guards than soldiers or military police.

''Some guards had proved to be hopeless - physically incapable of lifting a barrier or afraid of the dark,'' the report said. ''A significant proportion of those presented by security companies failed (defense ministry) vetting.''

The report also said: ''It is evident that there is a very serious problem with the caliber of people employed by private security firms, arising in part from the employment of guards with criminal records or propensities.''

The report cited:

-Low wages, high staff turnover and poor screening of applicants.

-Guards falling asleep as a result of working two straight shifts.

-A ''significant proportion'' of guards who failed military screening.

-Cases of vandalism, including smashing of windows.

The committee recommended the defense ministry not enter into any more contracts with private security firms until the industry is regulated by the government. It said it should consider replacing private firms with soldiers and police.

The parliamentary inquiry also was prompted by bombings at Inglis Barracks at Mill Hill in north London in August 1988 and at Clive Barracks at Tern Hill in Shropshire in February. One soldier died and nine were injured in the Mill Hill bombing, and one soldier was injured at Tern Hill.

After the inquiry began, there were attacks at military centers in Leicester and Halifax in February and two bombings last week in London.

The overwhelmingly Roman Catholic IRA is fighting to get British forces out of Northern Ireland and unite the Protestant-dominated province with the Irish Republic.