Pennsylvania Code
Title 34 - LABOR AND INDUSTRY
Part I - Department of Labor and Industry
Chapter 7 - ELEVATORS, LIFTS, ESCALATORS, DUMBWAITERS, HOISTS ANDTRAMWAYS
Subchapter M - AERIAL PASSENGER TRAMWAYS
CHAIR LIFTS, GONDOLA LIFTS AND SKIMOBILES
Section 7.445 - Towers

(a) Towers shall be located to conform to the profile of the terrain and to provide for the proper deflection of the hauling rope so that passengers will not be higher above the ground than necessary, nor so close as to encourage them to disembark at locations other than established stations.

(b) The adjustment of tower sheave heights, if made, shall be done in a manner to avoid overloading or underloading tower sheave units. In the furthering of this purpose, there shall be made available to the designer not only the profile of the natural terrain along the line but also profiles, approved by the owner, of the various anticipated snow depths for which the tramway is to be designed. The designer shall select one set of tower locations which will be suitable for all of such profiles. For each profile he shall determine the proper number and height of sheaves for each tower. The sheave units furnished for each tower shall be suitable for all of the profiles. Each tower shall be marked with the location of the assigned height for the sheave units for each profile, giving each profile a serial number or letter, such as A,B,C,D or the like. The operating instructions shall clearly state that when the sheaves on one tower are at location A, for example, then the sheaves on all towers shall also be at location A, and similarly for all other serial letters. The instructions shall also include a standard procedure for determining which serial designation to use to suit the snow conditions existing at any time. The owner shall make sure that these instructions are followed. After any such change the lift shall not be started until the horizontal alignment of the sheave units is checked.

(c) The interrelation between the location and height of towers, and design of sheave units and track cable saddles, shall be subject to the provisions of § 7.448(d) and (e) (relating to line structures).

(d) Towers and ropes shall be so arranged as to prevent the collision of passing carriers in the event of lateral swinging due to wind.

(e) The distance between two carriers, if swung ten degrees inward from the vertical, shall be at least two feet six inches. The distance between cables, for purposes of this check shall be considered as equal to the gage of the line.

(f) Since the skimobile line is supported by a trestle closely following the profile of the ground, most of the provisions of this section are irrelevant, except that the trestle shall be bridged over ski trails with an opening wide enough and high enough to permit the passage of skiers. The same is true of the monorail type, except that subsections dealing with wind action and lateral swing are relevant.

(g) When ski runs cross under the line, the tower shall be high enough to assure clearance for the skiers under the chairs or cars.

(h) Local wind conditions shall be taken into consideration in every instance.