7
Blocking
(a) While jacking, blocking should follow the load up or down to serve as an arresting device if the load falls.
(b) Wedges or shims should be used as necessary to ensure the load is completely supported at its blocking
points.
(c) Blocking shall be of sufficient thickness, width, and length to prevent shifting, toppling, or excessive
settlement of the load.
(d) Blocking shall be of sufficient strength to prevent crushing, bending failure or shear failure, and to
adequately transmit the load's weight to the supporting surface.
Horizontal Jacking
(a) Applications may arise where jacks are used in a position other than vertical. These applications, referred
to as horizontal jacking, require special attention.
(b) Horizontal jacking shall comply with the requirements of, Operating Practices, as applicable
(c) A plan shall be developed and communicated to affected personnel before horizontal jacking operations
begin. The plan shall consider but not be limited to the following:
1. Load weight
2. Effects of friction
3. Angle from horizontal plane
4. Load stability and control
5. Obstructions
6. Jack base support
7. Jack support
8. Load contact point
9. Handle clearance
10. Center of gravity of the load
11. Personnel safety
(d) When jacking horizontally, the base of the jack should be perpendicular to the direction of load movement.
(e) If multiple jacks are used, maintain parallel lines of force to prevent side loading of the jacks.
Note:
(a) No alterations, or modifications shall be made to this product.
(b) All replacement parts including pins, bolts, caps, and keepers shall meet or exceed the original equipment
manufacturer's specifications.
WARNINGS: Crush Hazard
(a) Personnel shall not place any part of their body between the jack and the load during lifting and lowering
of the load.
(b) Personnel shall not place any part of their body under a load supported by a jack.
(c) Personnel should not place any part of their body under blocking that is positioned to support the load,
when the load is supported by a jack.
(d) Personnel shall not straddle the handle of the jack.
(e) Personnel should ensure there is sufficient swing area to avoid pinch points while using the jack handle.
(j) Personnel should not be on a load supported by jacks.
(g) The jack operator should have firm footing and handle control while operating the jack.
(h) Unsynchronized operation of multiple ratchet jacks may produce increased or uncontrollable handle force.
(i) Personnel should avoid placing their head in the swing arc of the handle. Ratchet jack handles may
produce sudden kickback while lifting or lowering the load.
Ensure the handle load has been transferred to the jack before releasing the handle.
