This year, all residences in the District must be equipped with smoke detectors. Homeowners and landlords have until June 20 to install the early-detection devices.

The city's Smoke Detector Act, passed in 1978, requires smoke detectors in all homes, duplexes and apartments, hotels, motels, hospitals, nursing homes, prisons and residential-custodial care facilities in the District.

"At least 50 percent" of fire-related deaths could be avoided "if smoke detectors were installed and operating properly," according to local and national fire officials' estimates, said Inspector Chester Burke of the fire prevention division of the D.C. Fire Department.

There were 30 fire-related deaths in the District in 1980. Last year there were 2,214 residential fires, more than half of which occurred in multiple-family dwellings. There were 673 fires in single-family homes, 38 in hotels, 38 in hospitals, 55 in rooming houses, 24 in dormitories and 8 in nursing homes.

The new law requires that at least one smoke detector be installed and operating outside bedrooms near each sleeping area.

According to Burke, violators would be subject to a $300 fine or 10 days in jail if the fire chief decided to prosecute. The fire department won't "be going door to door" searching private homes, Burke said, but the department will inspect multiple-family dwellings for compliance.

"Most insurance companies are aware of the smoke-detector requirements here," Burke said, and "if there's ever a fire, our report will indicate whether smoke detectors were installed and whether the smoke detectors were operating or not."

None of the many brands of smoke detectors have been specifically recommended by the D.C. Fire Department, Burke said. Any unit approved by Underwriters Laboratories or Factory Mutual is acceptable, he said.

Ionization and photoelectric smoke detectors are the two basic types sold. While both have sensory devices that sound an alarm when unusually high levels of smoke are detected, the ionization type contains a radioactive element that some consumers' groups maintain is harmful. The fire department recommends either type, Burke said. He cited studies which show that the level of radiation in the ionization-type detector is "not a hazard and it should not be a problem."

The fire department will allow only electrically powered smoke detectors in existing and new multiple-family dwellings and in homes for which building permits were issued on or after Oct. 1, 1978.Battery-operated units "are acceptable at this time" for existing single-family homes, Burke said.

Burke said prices for smoke detectors range from $15 to $100, depending upon the brand or type purchased.

Information on the law or on smoke detectors can be obtained from the fire department at 745-2250.