Accident Prevention Manual
for Business & Industry:
Engineering & Technology
13th edition
National Safety Council
Compiled by
Dr. S.D. Allen Iske, Associate Professor
University of Central Missouri
CHAPTER 16
HOISTING AND CONVEYING EQUIPMENT
Hoisting Apparatus
• Definition: A hoisting apparatus is a device used to raise
and lower materials.
• Basic types:
• electric
• air
• hand-operated chain
Hoisting Apparatus (Cont.)
• General information:
• The safe load capacity of the hoist should be attached to the body
of the machine. The label for safe operation should be able to be
read from ground level.
• Loads should only be raised or lowered if the load is directly under
the hoist (centered).
• Personnel should NOT be allowed to enter the area directly under
the load.
Cranes
• Definition: A crane is a mechanical device designed to
raise, lower, and shift heavy objects through the use of a
long movable arm.
Cranes (Cont.)
• General information:
• A competent person must inspect all machinery and equipment
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prior to use to ensure safe operating condition; any deficiencies
repaired.
All parts of every crane should be of adequate strength for its rated
service.
Do NOT use a hoist or crane to transport people.
All equipment must be inspected and maintained to prevent
incidents.
Workers must be properly trained in the use of the hoist and all
safety policies/procedures must be followed at all times.
Cranes (Cont.)
• Overhead and gantry cranes constructed and installed
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after Aug. 31, 1971, must be in compliance with
ANSI/ASME B30.2.
Open hooks should not be used if there is a danger of the
tension decreasing during use.
Each independent hoisting unit shall have brakes
compliant with the standard.
The load rating should be clearly marked on each side of
the crane; each hoisting unit should have its rated load
marked.
An audible alarm and wind indicator should be utilized
and in visible sight of the crane operator.
Cranes (Cont.)
Design and construction:
• Arrange the cab and locate control and protective equipment so
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that all operating handles are within convenient reach of the
operator.
Each control lever should be marked with its action and direction of
control.
The controls should be self-closing to a neutral position.
Limiting devices to prevent overrunning safe limits
Provide for safe footing and accessways
Access to cab and/or bridge walkway by convenient fixed ladders,
stairways or platforms
Cab fitted with dry chemical or equivalent fire extinguisher
Accessible areas within swing radius barricaded to protect
employees from injury.
Cranes (Cont.)
Guards and limit devices:
• Gears and moving parts should be covered, or out of reach, during
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operation of the crane.
Traveling cranes must be equipped with an audible warning device
and a strobe light.
Large hooks should have handles affixed to them to allow the load
operator to manipulate the hook without danger to their
hand/fingers.
The hoisting motion must have an over-travel limit switch
No guard, safety, or other device shall be made inoperable except
for repairs or adjustments.
All guards and safety devices must be immediately activated after
completion of repairs or adjustments.
Cranes (Cont.)
General guidelines:
• Use hoisting ropes of recommended construction for crane or hoist
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service.
Inspection, testing, and maintenance should be performed by a
qualified person only.
Crane movement must be governed by a standard of code signals
between the crane signaler and crane operator.
Only one person should be authorized to signal the operator at any
given point in time.
Hand signals are preferred.
Overhead
Gantry Crane
Crane
Signals
Crane
Signals
Cranes (Cont.)
Selection and training of operators:
• Age: 18+
• Language: Understand spoken and written words/instructions.
• Physical: Physical fitness, visual acuity, depth perception, manual
dexterity, etc.
• Knowledge: Basic knowledge of the equipment, its usage,
inspection, maintenance, etc.
• Skills: Demonstrated proficiency in classroom and onsite. Maintain
a file that clearly documents the operator’s KSA.
• Note: Smoothness is a sign of a good crane operator.
Inspection
• Overhead and gantry cranes must be inspected according
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to ANSI/ASME B30.2.
New laws for operators of cranes are being enacted by
state laws and pending OSHA changes.
Certification of cranes by state laws are required at least
annually by certified crane inspector.
Repairs of cranes should be performed by qualified
individuals.
Do performance testing of hoisting equipment prior to
placing it in service.
Perform regular pre-shift and on-shift inspections to
ensure safe to operate.
Crane Operating Rules
• Review the list of Crane Manufacturer Association of
America, Inc. operating rules for crane operators.
• Review the maintenance safety rules from ANSI/ASME
B30.2 for Overhead and Gantry Cranes.
Overhead Cranes
• An overhead crane may be operated either from a cab or
from the floor.
• All control handles must be clearly identified by signs and
by shape or position so that an operator, while keeping
contact with the signaler, can identify each control by
touch.
• Keep controls in identical positions if multiple cranes are
used in one location.
Overhead Cranes (Cont.)
Overhead Cranes (Cont.)
• General information:
• It is important that the operator have a safe route to and from the
cab.
• In the event of an emergency, the operator must have a safe
egress regardless of the position of the crane on the runway.
• A fire extinguisher should be located inside the cab.
Storage Bridge and Gantry Crane
• Storage bridge cranes and gantry cranes travel on rails
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that are on ground level.
Gantry cranes typically have short spans, whereas
storage bridge cranes typically have large spans and may
be used to move large amounts of coal or ore.
Access to the cab is by ladder on one of the crane legs.
Keep track repaired and cleaned.
Provide warning devices to indicate crane travel.
Gantry crane
Storage Bridge and
Gantry Crane (Cont.)
• Guidelines:
• An audible alert should sound each time the travel controller handle
is moved from the off position.
• The operator should apply the rail clamps at any point in time when
the operator is not in the cab.
• Cranes of this nature are typically exposed to the elements;
therefore they require additional inspection and maintenance
procedures.
Monorail
• Definition: A monorail is a system consisting of one or
more independent trolleys, supported from or within an
overhead track, from which the hoists are suspended.
• Three types:
1. Hand-operated: material raised with hand-powered hoist and
trolley propelled by hand
2. Semi-hand-operated: power hoist and is moved horizontally by
hand
3. Power-operated: electrically actuated for both vertical and
horizontal movements
Monorail (Cont.)
Jib Crane
• Definition: A jib crane is capable of lifting, lowering, and
rotating a load within a circular arc by a rotating arm or jib.
The jib and trolley are typically supported or mounted
from a building wall, column or pillar.
• The hoist, which is used to lift the loads, is suspended
from the trolley that travels on the jib boom.
• Note: A qualified engineer should determine if the
structure is sufficient to support the crane.
Jib Crane (Cont.)
Derricks
• Main types of derricks
• a-frame derrick
• stiff-leg derrick
• guy derrick
• All derricks must have every part firmly anchored.
Derricks (Cont.)
Tower Cranes
• Tower cranes contribute to a large number of incidents.
• Common causes of incidents:
• Improper erection or dismantling of crane
• Exceeding load capacity
• Improper bracing
• Operator error
• Use during high winds
• Tampering with safety devices or limit switches
• Operators not knowing limitations of cranes or inadequate training
Tower Cranes
(Cont.)
Tower Cranes (Cont.)
• Safety guidelines:
• Appropriate steel or alloy for fabrication of crane structure
• Secure attachment of counterweights and safety ropes, rods or
chains.
• Only qualified, proficient personnel, familiar with the work
environment, may operate the crane.
• All moving parts should be guarded.
• Do not exceed lifting capacity.
• Account for weather conditions (wind forces, lightning, water weight
added to load, etc.).
• Management plays a key role in the safe use of tower cranes.
Tower Cranes (Cont.)
• Operation:
• Only personnel of recognized ability should operate a tower crane
(training and experience).
• Operator should have knowledge of crane construction and
performance specifications.
• Operators should never stand or climb outside of the cab if the
crane is in operation.
• Crane inspections prior to and during the loading.
• Know the load limits.
• Develop a plan for the lift as well as all aspects of crane use.
• Clear communication between all personnel during lifts.
Mobile Cranes
• Engineering marvel to accomplish many tasks in
construction with up to 1,000 ton capacity and length of
600 feet plus boom and jib.
• Mobile cranes may be powered by electricity, gasoline,
diesel fuel or steam. Each requires specific safety
guidelines.
• Outriggers must be utilized when required.
• Operators must exercise extreme caution when the crane
boom is at an extreme angle, as the load may contact the
boom.
Mobile Cranes (Cont.)
Mobile Cranes (Cont.)
• When the boom is fully extended, the load must not be
lowered to the side or at an angle to the crane body.
• If a crane is used to unload a truck, the truck must remain
in place while the load is lifted in case the load is too
heavy for the crane and the load must be lowered back
into the truck.
Mobile Cranes (Cont.)
• Safety data:
• 20% of construction fatalities are crane related. (Canadian data
and www.osha.gov)
• 90% of mobile crane injuries are linked to operator error.
• Other contributing factors:
• support failure: 30%
• failure to use outrigger: 20%
• crane failure: 10-20%
• Rigging: 4–15%
Mobile Cranes (Cont.)
• All injuries to employees: at least 25% involved with the
load and 10–15% involved with maintenance, refueling,
and so forth around the crane.
• Mobile cranes include locomotive cranes, crawler cranes,
wheel-mounted cranes, and industrial truck cranes.
• All mobile cranes have booms with load hoists and boom
hoists. Most cranes swing or rotate on a turntable. Power
is electric motor, steam, gasoline, or diesel engine.
Mobile Cranes (Cont.)
• Load Charts—every crane has a capacity plate or sign
noting the safe-load capacity at various radii from the
center pin of the turntable.
• Signs must be clearly legible to operator, signaler, and rigger.
Mount a boom angle indicator with freely suspended pointer.
• Pick must be within the limits prescribed in the chart.
• Capacity chart for operator must indicate boom length,
boom angle, and capacity.
• Safe access, good lighting, and warning devices
Mobile Cranes (Cont.)
• Operation:
• Extended riggers are considered part of counterweight on load
charts.
• Boom must never be swung too rapidly.
• Operating on soft or sloping ground or close to sides of trenches or
excavations is dangerous.
• Outriggers provide stability only on solid ground.
• Use caution when operating the boom at a high angle with a
suspended load. Do not let the load swing and strike the boom or
steel lattice.
• Use care in lowering an extended boom to ground.
• Center the hook over the load.
• Never use the crane for jerk piling and, when unloading from a
truck, don’t allow the truck to drive off from under the load.
• Consult manufacturer prior to any modifications of equipment.
Mobile Cranes (Cont.)
• Travel of cranes
• Cranes should not travel with a load suspended from the boom.
• If travel on public roads is necessary, the boom should point
forward and a flagman should be ahead of the unit.
• Electric wires
• Any overhead wires should be considered energized. Use a signal
person as well as warning devices.
• Inspection
• Routine inspections are important to determine deficiencies or
deterioration in components.
Aerial Baskets
• Aerial lift equipment is commonly used for working above
ground.
• These boom-mounted buckets, baskets, or platforms are
used in constructing and maintaining electric and
telephone lines.
• Increased use in harbor and port work, aircraft industry,
highway work, and maintenance work—painting,
sandblasting, and firefighting.
Aerial Baskets (Cont.)
Aerial Baskets (Cont.)
• Hazards:
• improper precautions concerning electrical hazards
• improper positioning of vehicle or outriggers
• overreaching
• not using PPE including safety belts
• moving vehicle with boom raised or insufficient clearance for boom
• swinging the boom or basket against overhead obstruction or
energized equipment
• moving boom into positions that interfere with traffic
• inadequately trained personnel
Aerial Baskets (Cont.)
• Operation:
• The lift, basket, and controls should be tested daily, prior to use to
determine controls are in safe working condition.
• Inspect for any defects.
• Mechanical equipment inspected daily for safe operation.
• Load limits of the boom and basket posted and not exceeded.
• Warm-up period and hydraulic system tested.
• Truck not moved unless boom is lowered and basket or ladder
cradled.
• Riding in basket while the truck is traveling shall not be permitted.
• Protect workers from unsafe positions during work.
• The operator must be cognizant of vehicular and pedestrian traffic.
Aerial Baskets (Cont.)
• Inspection
• All components of the basket, boom, cables, sheaves, leveling
devices, locking devices, controls, hydraulic system, and fluid
levels for any wear or defect. If defects are found, report them
immediately and perform appropriate repairs or corrections.
• Safeguards
• An aerial basket must be equipped with safety belts/lanyards and a
means for attaching the lanyard to the equipment.
• Lanyards should be long enough to allow movement only inside the
basket and prevent climbing onto the rim.
• Thoroughly train workers in the use of equipment before use.
• Proper footing for the wheels and outriggers should be provided.
Aerial Baskets
(Cont.)
• What potential hazards
are you able to identify in
this picture?
Crabs and Winches
• Safety concerns
• Install some form of brake or safety lowering device.
• Anchor portable units securely against the pull of the hoisting rope
or chain.
• The operator should be positioned away from the direct line of pull.
• Gears should be fully guarded.
• Barricade guards should be used to protect workers from flying
strands of wire.
• A small lever should be welded to the locking pawl to help prevent
hand/finger injuries.
Block and Tackle
• Safety factor of 10 is recommended for determining the
safe working load of Manila rope (falls) in a block-andtackle assembly.
• Allows for (1) error in estimating the weight of the load, (2) vibration
or shock in handling the load on the tackle, (3) loss of strength at
knots and bends, and (4) deterioration of the rope due to wear or
other causes.
• Governing factor is usually the safe working load of the
blocks rather than the falls (rope).
• Protect personnel from injuries during use of the pulley
and rope.
• Caution when using wire instead of fiber ropes.
Block and Tackle (Cont.)
• To find the required breaking strength for new rope:
• For each sheave 3 in. in diameter or larger, add 10% to the
weight of the load to compensate for friction loss.
• Divide this figure by the number of ropes or parts running
from the movable block.
• Multiply the resultant figure by a safety factor of 10.
EXAMPLE:
• A load weighs 2,000 lb, and the tackle consists of two double
blocks—four sheaves, four rope parts at the moveable block.
• Friction loss (10% per sheave) = 40% or 800 lb
• 2,000 + 800 = 2,800 lb., divided by 4 = 700 lb.
• Applying the safety factor of 10 (10  700) gives 7,000 lb., the
required breaking strength of the rope.
• Look up on the manufacturer’s rope tables the proper size rope for
the breaking strength that you have calculated.
Tiering Hoists and Stackers
• Tiering hoists (called stacking elevators, portable elevator,
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tiering machine, or platform hoist) are designed to raise
material in a vertical line on a moving platform.
Used in warehouses for piling and storing materials.
Operated electrically or manually.
Should have a braking device permitting safe lowering of
the platform. Workers do not ride platforms.
Protect the tiering machine from tipping over.
Conveyors
Conveyors (Cont.)
• Definition: A horizontal, inclined, or vertical device for
moving or transporting bulk material, packages, or
objects, in a path predetermined by the design of the
device and having points of loading and discharge.
Conveyors (Cont.)
• General precautions:
• Signed for loading points and safe load limit.
• Moving parts must be protected by guards.
• Underpasses should have sheetmetal ceilings.
• Special fire protection devices must be utilized at any point in which
a conveyor passes through a fire wall.
• Guard conveyors for handrails and toeboards.
• Protect workers from falling materials.
• Provide crossovers or underpasses with proper safeguards for
passage over or under all conveyors.
• All conveyors within 6’ 8” of a walkway that is meant to serve as an
exit route must be in compliance with NFPA 101, Life Safety Codes.
Conveyors (Cont.)
• Operation precautions:
• The start button should be located in an area where the operator
has the greatest field of view of the corresponding conveyor.
• Start-stop devices must be clearly labeled.
• If conveyor passes through a wall or floor, equip each side with
starting and stopping devices.
• Emergency stopping devices must not be located more than 75 ft
apart along walkways.
• Provide anti-run-away and backstop devices.
• Workers must wear properly fitting clothes and PPE.
• Control dust levels with exhaust hoods and good ventilation.
• Use proper electrical rated fixtures.
Conveyors (Cont.)
• Maintenance:
• The conveyor must be locked out, prior to any maintenance work
being performed. The worker should carry the only key to the lock.
• If two or more gangs will perform the work, they should follow
OSHA standard 1910.147 for lock out/tag out.
• Maintenance personnel should have access to change positions of
pulleys, sprockets, or sheaves to compensate for normal working
conditions.
• Provide guards for the on-running belt.
• Use fixed scrapers and revolving brushes to clean drums or pulleys
instead of workers attempts by hand.
• Use guards in front of pinch points.
• Guard sides to prevent contact.
Conveyors (Cont.)
• Frequent causes of injuries:
• attempting repairs on moving conveyors
• attempting to cross over moving belts
• attempting to ride moving belts
Conveyors (Cont.)
• Unique hazards:
• Dust explosions are a major concern in conveyor systems used for
transporting grain or similar products. (silo)
• Portable conveyors must be equipped with locking devices to keep
the belt and conveyor stable.
Types of Conveyors
• belt conveyors
• aerial conveyors
• slat and apron conveyors
• portable conveyors
• chain conveyors
• gravity conveyors
• shackle conveyors
• roll or wheel conveyors
• screw conveyors
• live roll conveyors
• bucket conveyors
• vertical conveyors
• pneumatic conveyors
Power Elevators
• New elevators or alterations or modifications require
compliance with code: ANSI/ASME A17.1 Safety Code for
Elevators and Escalators.
Power Elevators (Cont.)
• Two types of drives:
1. Electric drive
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traction drive (preferred method)
winding-drum drive
2. Hydraulic drive
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Energy is applied by means of a liquid under pressure in a cylinder
equipped with a plunger or piston.
New Elevators
• compliance with code ansi/asme a17.1
• safe and convenient access to the machine room and the
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pit
adequate lighting in the machine room and overhead
spaces
convenient electric outlets on the crosshead and in the pit
an inspection station with slow-speed up and down
operating buttons and emergency stop switch on the top
of the car for maintenance personnel and inspectors to
use
normal- and final-limit stops, interlocks on all hoistway
doors, contact on car door and emergency exits for the
car
Power Elevators
• Maintenance and hazard prevention:
• Winding drive
• Check stop functionality. (Motor does not stop and cable is wound beyond stop,
breaking the cable.)
• Check cables. (Cables are weakened as they are wound and subjected to friction
and bending forces.)
• Hoistways should be cleaned on a regular basis to minimize fire
hazards.
• Pits must have a minimum 2-ft clearance between the bottom of the
car and the pit.
Power Elevators (Cont.)
• Maintenance and hazard prevention (cont.):
• Enclose counterweight runways from a point not more than 1 ft
above the pit floor to a point at least 7 ft above the pit floor and
adjacent pit floors to protect workers from crushing hazards.
• Never use elevator pit for storage or to sweep debris into.
• Special precautions must be taken to prevent tripping incidents.
(passenger and freight)
• Provide lighting of at least 5 fc at the pit’s floor level.
• Emergency Stop switch shall be installed in every pit and shall be
reachable from the pit’s access door.
Power Elevators (Cont.)
• Maintenance and hazard prevention (cont.):
• Only qualified personnel should have access to door keys.
• Sides and tops of cars should be made out of metal or a fireresistant material.
• The car should be equipped with a maximum load capacity sign.
• Every elevator must have an emergency stop switch (red, clearly
identified) in the car.
Elevators—Emergency and Disabled
• Emergency procedure for
safely removing persons in
elevator.
• Incorporate the
requirements for
handicapped standard for
all new elevators.
Sidewalk Elevator
• Definition: a freight elevator for carrying material,
exclusive of automobiles, between a landing, a sidewalk,
or other area outside a building, and the floors below the
sidewalk or grade level.
• Presents hazards that are not easy to eliminate.
• Best to locate inside the building line or in an area not open to the
public.
• Conform to the Elevator Code.
• Except by permission of authorities, maximum dimensions
of openings should be 5 ft at right angles to, and 7 ft
parallel with building line. Side of opening nearest building
should be not more than 4 in. from building wall.
Dumbwaiters
• Definition: a hoisting and lowering mechanism equipped
with a car that
• (1) moves in guides and has a floor area not exceeding 9 ft2
• (2) has a compartment height not exceeding 4 ft
• (3) has a rated capacity not greater than 500 lb
• (4) is used exclusively for carrying materials.
• Can be hand or power operated.
Escalators
• Definition: a power-driven, inclined, continuous stairway
for raising or lowering passengers.
Escalator Safety Devices
• Emergency Stop buttons or other hand-operated switches
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having red buttons or handles, accessibly located at top
and bottom landings.
Key-operated button to start and stop unit.
Each escalator equipped with a speed governor that will
interrupt the power.
If tread chain breaks, sensing device should cut the
power.
Electrically released and mechanically applied brake able
to stop the fully loaded escalator.
Fire protection of escalator floor openings against spread
of fire and smoke is required by local building codes.
Man-Lifts
• Principal hazards:
• Rider may be carried over the top.
• Rider unable to make emergency stop.
• Rider jumps off early/late.
• Rider strikes head on surface if not conical hood.
• Rider unable to reach destination due to power failure or belt
stoppage.
• Parts of man-lift fail or operate unsafely.
Man-Lifts (Cont.)
• Incident prevention:
• Construct, maintain and operate man-lift in accordance with
ANSI/ASME A90.1 Belt man-lifts.
• Use a safety factor of 6 on each step.
• Emergency landings should be provided every 25 ft or less.
• Guardrails should be used at floor openings.
• Maximum speed should not exceed 80 fpm.
• Conduct inspections by competent person every 30 days.