[Gravityloss]

At least over here, in maintenance ladders over a few stories high there's a central C shaped track where you attach a metal car about the size of a fist. Then you attach your harness to the car. The car can't come out of the rail. It also has a mechanism that it only moves if you pull it outwards.

Makes climbing really easy and safe. Technically you don't even need to use your hands for anything .