Moving large, heavy loads is crucial to today’s manufacturing and construction industries. Much technology has been developed for these operations, including careful training and extensive workplace precautions. There are significant safety issues to be considered, both for the operators of the diverse “lifting” devices and for workers in proximity to them. This course is a starting point for finding information about these devices and their operation.
OSHA’s standard applies to power-operated equipment used in construction work that can hoist, lower, and horizontally move a suspended load unless such equipment is specifically excluded from coverage.
Cranes Types
The types of cranes and derricks in the next few tabs are the most commonly used in construction and covered by OSHA’s crane standard.
Mobile Cranes
These cranes use a lifting device incorporating a cable suspended latticed boom or hydraulic telescopic boom designed to be moved between operating locations by transport over the road. Mobile cranes include crawler mounted, wheel-mounted, rough terrain, all-terrain, commercial truck-mounted, and boom truck cranes.
Tower Cranes
Lifting structures that utilize a vertical mast or tower to support a working boom (jib) in an elevated position. Loads are suspended from the working boom. While the working boom may be of the fixed type (horizontal or angled) or have the luffing capability, it can always rotate to swing loads, either by rotating on the top of the tower (top-slewing) or by the rotation of the tower (bottom slewing). The tower base may be fixed in one location or ballasted and moveable between locations. Tower cranes include those with a fixed jib (hammerhead boom), those with a luffing boom, and self-erecting tower cranes.
Articulating Cranes
Also known as knuckle-boom cranes and loader cranes. These are cranes whose boom consists of a series of folding, pin-connected structural members, typically manipulated to extend or retract by power from hydraulic cylinders.
All Derricks
This crane is composed of a tower that doesn’t actually bend but instead pivots at the base. The tower is usually made up of crisscrossing steel pipes and braces. This gives the crane a great deal of strength using very little structure. Four lines are connected to the tower; the crane tower can move in every direction because the lines are independent of one another. Hanging over the end of the tower is a single fifth line that has a hook or other attachment on the end. This fifth line moves up and down and attaches to loads.
Controlling Employers
The employer that is a prime contractor, general contractor, construction manager or any other legal entity which has the overall responsibility for the construction of the project (its planning, quality, and completion) is considered the controlling employer, sometimes called the controlling entity.
- The controlling entity is responsible for seeing that the ground conditions are adequate to support the equipment.
- The controlling entity must also inform the user and the operator of the equipment of the location of hazards beneath the equipment set-up area (such as voids, tanks, utilities) if those hazards are identified in documents (such as site drawings, as-built drawings, and soil analyses) in the possession of the controlling entity (whether at the site or off-site) or of any other hazards known to the controlling entity.
- The controlling entity must also establish a system to coordinate the operations of two cranes that operate within each other’s working radius.
The A/D Director
All assembly/disassembly operations must be directed by an individual who meets the criteria for both a competent person and a qualified person, or by a competent person who is assisted by one or more qualified persons. The A/D director must understand the applicable assembly/disassembly procedures. The A/D director must take the following precautions to protect against potential hazards associated with the operation.
