In the Final Rule, OSHA determined that lockout is a surer means of ensuring equipment is de-energized than tagout and is the preferred method. However, the Agency also recognized that tagout will nonetheless need to be used instead of lockout where the energy control device cannot accept a locking device. Where an energy control device has been designed to be “lockable”, the standard REQUIRES that lockout be used unless tagout can be shown to provide “full employee protection,” that is, protection equivalent to lockout. But what does OSHA consider to be “locakable”?