Injuries related to snowmobiles, motorcycles and moose-car collisions have increased. The aim of the present thesis was to analyse mechanisms and consequences in fatal and non-fatal accidents of these types, and to penetrate possible preventive measures. Snowmobiles The median age of the injured was 30 and of the killed 32, males pre­dominating. A majority of the accidents occurred during weekends, and especially the fatal accidents occurred after dark. The extremities were the most commonly injured parts of the body, however, drowning, crushed chest and cranial injuries caused most of the fatalities. Among the fatalities, four out of five were under the influence of alcohol. The present Swedish laws regarding snowmobiles seem well motivated. "Built-in" safety measures in the construction of the snowmobiles, pro­perly designed snowmobile tracks and functional search and rescue sys­tems could reduce the injuries. Motorcycles The median age was 19 years for both the traffic injured and the kil­led. Half of the traffic accidents were collisions with other motor ve­hicles. In the fatally injured group, also collisions with fixed road­side objects were common. Of the fatally injured, more than every fifth person died in an accident where alcohol was an influential factor. In the injured group, lower extremity injuries (especially in off-road riding) were common and among the fatalities most riders died from injuries to the head or chest. Out of one thousand motorcycle riders interviewed, 45% reported wobbling experiences (8% reported severe wobbling). Possible injury reducing measures include increasing the licensing age, more discriminating driving test, "built-in" restriction of the motorcycle's top speed, elimination of motorcycles prone to wobbling, and a more intensive traffic supervision (speeding, alco­hol). Moose-car collisitions The median age of the drivers was 38 years. Most collisions happened at dusk or when dark (3/4). The median collision speed was 70 km/h. The damage to the car was typical, the roof and the windshield pillars were deformed downwards and backwards. The broken windshield was often pressed into the passenger compartment. Most of the injured car occu­pants suffered cuts predominantly to the head and upper extremities. Nearly all the fatally injured died of head and neck injuries. The injuries may be reduced by strengthening the roof and the windshield pillars, and by introducing anti 1 acerati ve windshields. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1985</p> / digitalisering@umu