ski touring and ski mountaineering helmet 
Helmet use has become widespread in alpine skiing in recent years. This is a little less true for cross-country skiing. However, the dangers are very high in the mountains. Fall while skiing down and falling projectiles along the mountain walls. Manufacturers of ski touring and ski mountaineering helmets now make very lightweight helmets that can be worn all the way out without constraint. For the most part, and this is mandatory in ski mountaineering competitions, they meet the dual standards of mountaineering (CE EN 12492) and skiing (CE EN 1077, class B).
Speck-sports has selected the best brands of cross-country ski helmets and double standard ski mountaineering helmets among : Dynafit, Camp, Skitrab, Kong, Salomon...