30 CFR § 57.10008
Riding tramways.
Persons other than maintenance persons shall not ride aerial tramways unless
the following features are provided.
(a) Two independent brakes, each capable of holding the maximum
load;
(b) Direct communication between terminals;
(c) Power drives with emergency power available in case of primary
power failure; and
(d) Buckets equipped with positive locks to prevent accidental
tripping or dumping.