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When conventional means
of access (e.g., scaffolds, ladders) are unsafe, personnel hoisting
operations that comply with OSHA standards are allowed. Employee
safety — not practicality or convenience — must determine an
employer’s choice of method.
Because using cranes or derricks to hoist personnel poses a serious
risk to the employees being lifted, any cranes and derricks that
hoist personnel must conform to the following:
• Be placed on a firm foundation;
• Be uniformly level within 1 percent of level grade;
• Have a minimum safety factor of seven for the load line (wire
rope) of the crane or derrick (this means it must be capable of
supporting seven times the maximum intended load);.• Move the
personnel platform slowly and cautiously without any sudden jerking
of the crane, derrick, or platform;
• Have rotation-resistant rope with a minimum safety factor of 10;
and
• Have all brakes and locking devices on the crane or derrick set
when the occupied
personnel platform is in a stationary working position.
In addition, the combined weight of the loaded personnel platform
and its rigging must not exceed 50 percent of the rated capacity of
the crane or derrick for the radius and configuration of the crane
or derrick.
The crane operator must always be at the controls when the crane
engine is running and the personnel platform is occupied. The crane
operator also must have full control over the movement of the
personnel platform.
Employers must ensure the following:
• Cranes and derricks with variable angle booms must have a boom
angle indicator that is visible to the operator.
• Cranes with telescoping booms must be equipped with a device to
clearly indicate the boom’s extended length, or the load radius to
be used during the lift must be accurately determined prior to
hoisting personnel.
• Cranes and derricks must be equipped with (1) an anti-two-blocking
device that prevents contact between the load block or overhaul ball
and the boom tip, or (2) a two-block damage-prevention feature that
deactivates the hoisting action before damage occurs.
A qualified engineer, or a qualified person competent in structural
design, must design platforms used for lifting personnel to do the
following:
• Support platform weight and at least five times the maximum
intended load.
• Minimize tipping caused by personnel movement on platforms by
having an appropriate suspension system.
• Keep tools, materials and equipment from falling on employees
below by having a standard guardrail system that is enclosed from
the toe board to the mid-rail.
Platforms also must have the following:
• Inside grab rail;
• Permanent marking or plate that clearly indicates the
platform’s weight and rated load capacity or maximum intended load;
• Access gate, if provided, that does not swing outward during
hoisting and is equipped with a restraining device to prevent
accidental opening; and
• Adequate headroom for employees. In addition, the OSHA standard
requires the following:
• All personnel must wear hard hats and have overhead protection on
the platform when exposed to falling objects.
• All rough edges on the platform must be ground smooth to prevent
injuries to employees.
• All welding on the personnel platform and its components must be
performed by a qualified welder who is familiar with weld grades,
types, and materials specified in the platform design.
Load restrictions: The loading of personnel platforms must conform
to the following requirements:
• Personnel platforms must not be loaded in excess of their rated
load capacity or maximum intended load as indicated on permanent
markings.
• Only personnel instructed in the requirements of the standard and
the task to be performed — along with their tools, equipment, and
materials needed for the job — are allowed on the
platform.
• All materials and tools must be secured and evenly distributed to
balance the load while the platform is in motion.
Rigging
Rigging for personnel platforms must conform to the following
requirements:
• Legs of bridles must be connected to a master link or shackle so
that the load is evenly positioned among the bridle legs when a wire
rope bridle is used to connect the platform to the load line.
• Bridles and associated rigging for attaching the personnel
platform to the hoist line must not be used for any other purpose.
• Hooks and other attachment assemblies must be closed and locked to
eliminate the hook throat opening (an alloy anchor-type
shackle with a bolt, nut and retaining pin may be used as an
alternative).
Inspections and Tests
Before hoisting employees, crane or derrick operators must conduct a
trial lift of an unoccupied personnel platform immediately prior to
placing personnel on the platform by taking the following
actions:
• Load the platform at least to its anticipated lift weight during
the trial lift.
• Start the lift at ground level, or at the location where employees
will enter the platform, and proceed to each location where the
platform will be hoisted and positioned.
• Check all systems, controls and safety devices to ensure that they
are functioning
properly and that there are no interferences.
• Ensure that all boom or hoisting configurations necessary to reach
work locations will allow operators to remain under the 50 percent
load limit of the hoist’s rated capacity.
• Repeat the lift before hoisting personnel if a crane or derrick is
moved to a new location
or returned to a previous location.
After the trial lift?
After the trial lift, employers must ensure that the personnel
platform is hoisted a few inches and inspected to ensure that it is
secure and properly balanced. Before workers are hoisted, employers
must ensure that a check is performed to ensure the following:
• Hoist ropes are free of kinks;
• Multiple part lines are not twisted around each other;
• Primary attachment is centered over the platform;
• No slack is in the wire rope; and
• All ropes are properly seated on drums and in sheaves. Immediately
after the trial lift, an employer designated competent person must
conduct a thorough visual inspection
of the crane or derrick, the personnel platform, and the crane or
derrick
base support or ground to determine if the lift test exposed any
defects or produced
any adverse effects on any component or structure. The competent
person must correct any defects found during inspections before
personnel are hoisted. A competent person is one who
can identify existing and predictable hazards in the workplace and
is authorized to correct them (see 29 CFR 1926.32(f)).
Employers must ensure that the platform and rigging are proof tested
to 125 percent of the platform’s rated capacity in the following
circumstances:
• When initially brought to a job site;
• After any repair or modification; and
• Prior to hoisting personnel.
Proof testing is achieved by holding the loaded platform, with the
load evenly distributed,
in a suspended position for five minutes. Then a competent person
must inspect the platform and rigging for defects.
If the competent person detects any problems, they must be corrected
and another proof test conducted. Operators must not hoist personnel
until proof testing requirements are met.
Must employers meet with workers before hoisting operations begin?
Before any hoisting operations are performed, employers must meet
with all workers involved in personnel hoisting operations — crane
or derrick operators, signal persons, employees to be lifted, and
the person responsible for the hoisting operation — to review all of
the OSHA requirements in 29 CFR Part 1926.550(g) and the procedures
everyone must follow. Employers must hold this meeting before the
trial lift at each new worksite and repeat it for all employees
newly assigned to the operation.
Safe Work Practices
Workers can contribute to safe personnel hoisting operations and
help reduce the number of associated accidents and injuries.
Employees must follow the following safe work practices:
• Use tag lines unless their use creates an unsafe condition.
• Keep all body parts inside the platform during raising, lowering
and positioning.
• Make sure a platform is secured to the structure where work is to
be performed before entering or exiting it, unless such securing
would create an unsafe condition.
• Wear a personal fall arrest system. The lanyard must be attached
to the lower load block or overhaul ball or to a structural member
within the personnel platform.
If the hoisting operation is performed over water, the requirements
in 29 CFR Part 1920.106 apply.
• Stay in view of, or in direct communication with, the operator or
signal person. How operators make lift operations safer?
To make lift operations safer, crane and derrick operators must
adhere to the following safe work practices:
• Do not leave crane or derrick controls when the engine is running
or when the platform is occupied.
• Stop all hoisting operations if there are any indications of
danger, including weather conditions.
• Do not make any lifts on another load line of a crane or derrick
that is being used to hoist personnel. FSM |
