The objectives of this study are to estimate smoke alarm coverage and adherence with national guidelines in low- to mid-value owner-occupied residences, and to identify resident demographic, behavioral, and building characteristics and other fire and burn safety practices associated with smoke alarm utilization. Baseline visits were conducted with 779 households in King County, Washington, for a randomized trial of smoke alarm functionality. Presence, functionality, features, and location of pre-existing smoke alarms were ascertained by staff observation and testing. Household and building descriptors were collected using questionnaires. Households were classified by presence of smoke alarms, functional alarms, and functional and properly mounted alarms placed in hallways and on each floor but not in recommended avoidance locations. Smoke alarms were present in 89%, and functional units in 78%, of households. Only 6-38% met all assessed functionality and placement recommendations. Homes frequently lacked alarms in any bedrooms or on each floor. Building age, but not renovation status, was associated with all dimensions of smoke alarm coverage; post-1980 constructions were 1.7 times more likely to comply with placement recommendations than were pre-1941 homes (95% CI: 1.1-2.6). Respondent education and race/ethnicity, children <5 years, residency duration, number of floors, wood stoves and fireplaces, number of smoke alarms, recency of smoke alarm testing, carbon monoxide monitors, and fire ladders displayed varying relationships with alarm presence, functionality, and placement. Strategies for maintaining smoke alarms in functional condition and improving compliance with placement recommendations are necessary to achieve universal coverage, and will benefit the majority of households.