Accidents happen — and they also kill enough people to rank as the No. 1 cause of death for those ages 1 to 42, according to the National Safety Council. Accidents are the fifth-leading cause of death across all age groups, topped only by a spate of illnesses that include heart disease and cancer. And it’s not the heavy-machinery operators, high-rise window washers or electricians who most frequently succumb to fatal accidents. The vast majority of accidental deaths happen at home or in the community — not at work — with the top five causes often stemming from routine activities.