41. For the maintenance, cleaning or repair of the head of a mechanized feller,(1) a working procedure must be established;
(2) the worker performing the work must have received the proper training;
(3) the worker must lock off or control all sources of energy in order to avoid any motion of the forestry machine, the felling head or its parts.
The procedure for locking off or controlling sources of energy must be approved, in writing, by a qualified person. A “qualified person” is a person who understands how a complex system such as an electrical, pneumatic or hydraulic system works and, where applicable, is able to make recommendations or take action in complete safety.