EDITORIAL : PREVENTING A TRAGEDY FIRE DEPARTMENTS ARE RIGHT TO CHECK OUT SPRINKLERS.

CITY and county fire officials are acting appropriately as they spearhead sweeping inspections of one model of fire sprinkler head after credible reports that it might not activate in a blaze.

Lives could be at stake and public safety is a top concern of fire departments and other units of local government.

Ineffective or unreliable fire suppression devices might be worse than having nothing at all, because they may lead to a false sense of security and lull people into relaxing their vigilance.

In the city of Los Angeles alone, more than 750,000 of the questionable sprinkler heads have been installed since 1983 - in schools, apartments, hotels, offices and other buildings, according to estimates from the Department of Building and Safety. Untold numbers were installed in other cities and unincorporated areas of the county.

An inspection program of such scope might require hundreds of building owners to get their automatic sprinkler systems tested, perhaps at significant inconvenience and cost.

We trust that fire and building and safety officials will make every effort to assist tenants and owners during examinations of the sprinkler heads.

We also commend fire departments and other local authorities for their response after the county Fire Department reported that one of the problematic Omega brand sprinkler heads didn't operate in a West Hollywood fire earlier this year.

We suspect most people would agree that the probe will be well worth the inconvenience and cost. Loss of life in a fire is always tragic, and would seem more so if it were due to the failure of systems designed to work at the first sign of trouble.

The particular model of sprinkler head under scrutiny reportedly had a 31 percent failure rate in Underwriters Laboratories tests and a 35 percent failure rate in tests conducted for Virginia's Fairfax County Fire and Rescue Department. Those figures are very troubling.

``Members of the public who have an automatic sprinkler system have invested in the highest degree of fire protection,'' said Jimmy Hill, fire marshal in the Los Angeles Fire Department. ``They should have the peace of mind of knowing that the system is fully functional.''

Hill is right. People who own or use sprinkler-equipped buildings should enjoy the comfort of knowing that the safety equipment will work in an emergency.