San Francisco's law, which took effect last year, compels owners of commercial and multifamily buildings built before 1979 to notify tenants before exterior paint work is performed. The law assumes that such buildings contain lead paint, unless owners can show otherwise through certified tests.

Owners or contractors also must furnish tenants with a U.S. Environmental Protection Agency booklet, ``Protect Your Family From Lead in Your Home,'' and post notice of lead-paint work on building exteriors.

A federal law that went into effect in June requires owners of slightly older buildings, those built before 1978, to divulge in new leases the existence of lead paint -- regardless of whether paint work is planned. The law also applies when any pre-1978 property is sold.

Consumers need to be cautious about interior painting in older homes.

The EPA recommends using a respirator, protective clothing and special filter-equipped vacuum cleaners when sanding lead paint inside. It suggests wet sanding through use of special abrasive paper or sponges available from home improvement stores.