The isolation of potential energy involving gravity shall be accomplished by placing blocks made
of metal, wood or other suitable materials under the mechanism or by pinning the linkages in a
position where gravity will not cause the mechanism to fall.
B. Springs The isolation of
potential energy involving springs shall be accomplished by blocking the spring in a safe
position, either by pinning or clamping, or by securing the device in some other manner to
eliminate the potential for unrestricted or undesired movement.
C.