Approximately 80%-90% of all fire-related fatalities take place in residential occupancies. The risk groups are well known, but the effectiveness of different measures has been less investigated. In this article, fire investigations from 144 unintentional fatal residential fires have been systematically analyzed and technical measures that would have been effective in preventing each fatality have been identified. The result shows that, generally, a thermally activated suppression system (e.g. sprinkler) has the highest potential effectiveness (68%) followed by a detector-activated system in bedroom and living room (59%) or smoke alarm (37%). For smokers with home care, however, the potential effectiveness of a thermally activated suppression system and home smoke alarm was significantly lower (31% and 14%, respectively). This indicates that different measures are effective for different groups. In one-fifth of the cases, the victim could have evacuated but chose not to do so, primarily to attempt to extinguish the fire.