District of Columbia residents have just nine days to install smoke detectors in their homes because of a City Council law passed three years ago.

The law requires all Washington homeowners to install either electrical or the less expensive battery-operated commercial smoke detectors near each bedroom in their single-family homes. Hotels, motels, hospitals, nursing homes and apartments must be equipped with electrical smoke detectors for each sleeping area, either in the room itself or in hallways outside.

Despite the new requirement, the D.C. fire marshal's office said yesterday there will be no inspections of single-family homes once the smoke detector law takes effect a week from Saturday. But those who choose to violate the law could face fines of up to $300 for each day the smoke detector is not in place if it is discovered they do not have detectors.

Lt. William H. Price of the fire marshal's office said that firefighters responding to fires after June 20 will be authorized to inspect for smoke detectors and cite violators. Price also said that inspectors from various other city agencies who routinely enter private homes -- mostly building inspectors checking plumbing and electrical wiring or issuing construction permits -- would all be authorized to check for smoke detectors as well.

Apartment buildings, commercial buildings and health care families are already routinely inspected.

People who do not have smoke detectors will be violating four separate D.C. codes. But violations of the separate codes carry different penalties and the penalty will depend on which type of code inspector discovers the violation. Under the city's housing regulations, violators are subject to a $300 fine and 10 days in prison. Under the city's electrical code, violators of the smoke detector law only would be subject to $25 for each day the smoke detector is not in place.

The stiffest fine -- $300 and 10 days imprisonment for each day the smoke detector is missing -- is authorized under the city's building code.

The city's smoke detector law required all new buildings constructed after 1978 to be equipped with smoke detectors. All city government buildings were required to have smoke detectors as of June 20, 1980.

The District and 22 states now have laws requiring smoke detectors in newly constructed facilities, according to the U.S. Fire Administration's Federal Emergency Management Agency.

But Washington is one of only six jurisdictions with a smoke detector law that applies to existing buildings and private homes, the agency said.

Both Maryland and Virginia have state laws requiring smoke detectors in new buildings. Maryland also requires smoke detectors in some, but not all existing buildings, depending on whether they are in compliance with other fire codes.

Some local jurisdictions within those states, however, have passed their own stricter smoke detector requirements, including some of those in the Washington area.

Under the District law, apartment owners -- not tenants -- will be required to install the smoke detectors. Only electric-powered detectors are allowed in apartment units, because at the time the bill was passed some council members feared that landlords would not take proper care to periodically check battery-operated detectors.

Price and council member David Clarke (D-Ward 1) said that many individual fire insurance policies will not recognize claims if a house was not equipped with a smoke detector. In the case of a fire that does damage to nearby buildings, the home owner without a smoke detector could be found negligent and liable for the damages.