Two problems solved by our patented (US Pat 7410101) wireless Lock which solves legally requirements.
1. Workers have to climb up and down 300 feet of wind turbines to perform lock out tag out. The law does not allow a second person to do so on behalf of a working person.
2. Group lock - to conduct lock out tag out of more than one person - a lock box and many locks.
A prototype exists and and subscription system to meet legal requirements.