Safety Training - beyond compliance
Specific training helps workers understand their roles and responsibilities, gives an overview of specific hazards to which they may be exposed and helps them to be able to apply mitigation strategies against those hazards.
Your employees should demonstrate and continue to demonstrate their understanding of the subject matter. For example, if your employees do not know how to don and adjust a harness properly, have no concept of fall clearance, are connecting to insufficient anchor points, and/or are not performing satisfactory inspections of the equipment, the training will be deemed inefficient.
Safety training is not just a good idea, WHS/OHS regulations require that your personnel be trained. Often, it is argued that training is unnecessary because the employee in question had many years of experience with the given work.
Years of experience will mean that they most likely know how to perform a task, but do they know how to perform it safely?