Section 2.21 Counterweights
Where tie-rods are used, a minimum of two shall be provided, which shall pass through all weight sections. Tie-rods shall be provided with a locknut and cotter pin at each end.
This protection shall be provided by either of the following:
(a) a guiding means wherein no failure or wear of the guiding member shall allow the counterweight to be displaced more than 13 mm (0.5 in.) from its normal running position
(b) a retention means that shall be permitted to be integral with the guiding means
Compensation means, such as compensating ropes or chains or other mechanical means and their attachments (except for safety hooks, where used) to tie the counterweight and car together, shall be capable of withstanding, with a factor of safety of 5, any forces to which the means is subjected with the elevator at rest.
The maximum suspended weight of the compensation means with the car or counterweight at the top of its travel and one-half of the total weight of the tension sheave assembly, where used, shall be included.
The compensation means, connection, building structural members, and fastenings shall be capable of withstanding the maximum forces to which they are subjected due to car or counterweight buffer engagement or safety application with a factor of safety not less than 2.5.