Mont. Code Ann. § 23-2-733

23-2-733 . Duties of operator regarding ski areas. (1) Consistent with the duty of reasonable care owed by a ski area operator to a skier, a ski area operator shall:

(a) mark all trail grooming vehicles by furnishing the vehicles with flashing or rotating lights that must be in operation whenever the vehicles are working or are in movement in the ski area;

(b) mark with a visible sign or other warning implement the location of any hydrant or similar equipment used in snowmaking operations and located on ski slopes and trails;

(c) maintain one or more trail boards at prominent locations at each ski area displaying a map of that area's network of ski slopes and trails, the boundaries of the ski area, and the relative degree of difficulty of the ski slopes and trails at that area;

(d) post a notice requiring the use of ski-retention devices;

(e) designate at the start of each day, by trail board or otherwise, which ski slopes and trails are open or closed and amend those designations as openings and closures occur during the day;

(f) post in a conspicuous location the current skier responsibility code that is published by the national ski areas association;

(g) post a copy of 23-2-736 in a conspicuous location; and

(h) mark designated freestyle terrain with a symbol recognized by the national ski areas association.

(2) Nothing in this part may be construed to impose any duty owed by a ski area operator to a trespasser or an unauthorized user of a ski area.