DIFF Subgroup
E01H 4/023 Full Title
Working on surfaces of snow or ice in order to make them suitable for traffic or sporting purposes, e.g. by compacting snow (production of artificial snow F25C3/04) > for sporting purposes, e.g. preparation of ski trails; , e.g. devices adapted for ski-trails (production of snow or ice for winter sports or similar recreational purposes F25C3/00)