Washington Administrative Code › Title 296 - Labor and Industries, Department of › Chapter 296-24 - General safety and health standards › Part D - MATERIALS HANDLING AND STORAGE, INCLUDING CRANES, DERRICKS, ETC., AND RIGGING › Handling and Storage-Cranes, Derricks, Etc › Section 296-24-23533 - Crane and derrick suspended personnel (work) platforms

Current through Register Vol. 24-14, July 15, 2024
(1)
Scope and application.
This
				  standard applies to the design, construction, testing, use and maintenance of
				  personnel platforms, and the hoisting of personnel platforms on the load lines
				  of cranes or derricks.
(2)
Definitions.
For the purposes of this section, the following
				  definitions apply:
Failure.
Load refusal, breakage, or separation
					 of components.
Hoist
(or hoisting)
.
All crane or derrick functions such as lowering, lifting,
					 swinging, booming in and out or up and down, or suspending a personnel
					 platform.
Load refusal.
The point where the ultimate
					 strength is exceeded.
Maximum intended load.
The total load of all
					 employees tools, materials, and other loads reasonably anticipated to be
					 applied to a personnel platform or personnel platform component at any one
					 time.
Runway.
A firm, level surface designed,
					 prepared, and designated as a path of travel for the weight and configuration
					 of the crane being used to lift and travel with the crane suspended platform.
					 An existing surface may be used as long as it meets these
					 criteria.
(3)
General
				  requirements.
The use of a crane or derrick to hoist employees on a
				  personnel platform is prohibited, except when the erection, use, and
				  dismantling of conventional means of reaching the worksite, such as a personnel
				  hoist, ladder, stairway, aerial lift, elevating work platform or scaffold,
				  would be more hazardous, or is not possible because of structural design or
				  worksite conditions.
(4)
Operational criteria.
(a) You
				  must perform hoisting of the personnel platform in a slow, controlled, cautious
				  manner with no sudden movements of the crane or derrick, or the
				  platform.
(b) You must ensure that
				  load lines are capable of supporting, without failure, at least 7 times the
				  maximum intended load, except that where rotation resistant rope is used, the
				  lines must be capable of supporting without failure, at least 10 times the
				  maximum intended load. The required design factor is achieved by taking the
				  current safety factor of 3.5 and applying the 50% derating of the crane
				  capacity.
(c) You must engage load
				  and boom hoist drum brakes, swing brakes, and locking devices such as pawls or
				  dogs when the occupied personnel platform is in a stationary working
				  position.
(d) You must equip cranes
				  and derricks with variable angle booms with a boom angle indicator, readily
				  visible to the operator.
(e) You
				  must equip cranes with telescoping booms with a device to indicate clearly to
				  the operator, at all times, the boom's extended length, or you must make an
				  accurate determination of the load radius to be used during the lift prior to
				  hoisting personnel.
(f) You must
				  use a positive acting device which prevents contact between the load block or
				  overhaul ball and the boom tip (anti-two-blocking device), or you must use a
				  system which deactivates the hoisting action before damage occurs in the event
				  of a two-blocking situation (two block damage prevention feature).
(g) You must ensure that the load line hoist
				  drum has a system or device on the power train, other than the load hoist
				  brake, which regulates the lowering rate of speed of the hoist mechanism
				  (controlled load lowering). Free fall is prohibited.
(h) You must ensure that the crane is
				  uniformly level within 1% of level grade and located on firm footing. You must
				  ensure that cranes equipped with outriggers have them all fully deployed
				  following manufacturer's specifications, insofar as applicable, when hoisting
				  employees.
(i) You must ensure that
				  the total weight of the loaded personnel platform and related rigging does not
				  exceed 50% of the rated capacity for the radius and configuration of the crane
				  or derrick.
(j) The use of machines
				  having live booms (booms in which lowering is controlled by a brake without aid
				  from other devices which slow the lowering speeds) is prohibited.
(k) Multiple-part line block: When a
				  multiple-part line block is in use, you must use a substantial strap between
				  the crane hook and common ring, shackle, or other equivalent device, to
				  eliminate employee exposure to the lines running through the block, and to the
				  block itself.