Cranes SP# 1910.179
2.0 Scope and Applicability
5.0 General Responsibilities
6.2 General Provisions
6.2.2 Types of Cranes Used in NCDENR
6.2.3 Hazards Common to Cranes
6.2.4 Crane Safety
6.3 Specific Responsibilities
6.3.4 Safety Risk Management
6.3.5 Division of Purchase and Services
Appendix A: Specific Operating Practices
Appendix B: Hazards Common to Cranes
Appendix C: Hazard Prevention Requirements for Crane Safety 19
The purpose of this safety policy is to establish
crane operation procedures for North Carolina Department of
and Natural Resources (NCDENR) employees who operate or work in close
2.0 Scope and Applicability
A variety of cranes are used in NCDENR operations
from bridge and road construction to indoor material handling. Cranes
an important category of machinery in NCDENR because of the
and economic benefits associated with crane use. However, cranes can be
dangerous pieces of equipment if basic hazards are ignored.
This safety policy provides guidelines for avoiding hazards associated with crane operation. It includes provisions for training, discussion on the types of cranes used in NCDENR, listing of hazards common to cranes, and discussion on crane safety.
This document also details the areas of responsibility for manager, supervisors, employees, and Safety Risk Management within NCDENR.
This safety policy affects crane operators, riggers, signalers, and any employee who as a result of his or her job duties works with or near cranes.
This safety policy is established in accordance
Occupational Safety and Health Standards for General Industry (29 CFR
and Occupational Safety and Health Standards for Construction Industry
(29 CFR 1926.550). NC Department of Labor, A Guide to Crane Safety, 2004,
It is the policy of NCDENR to provide a place of
employment free from recognized hazards that cause or are likely to
death or serious physical harm to employees or the public. Therefore,
cranes will not be operated by untrained employees or in a manner that
endangers employees or the public. When crane hazards exist that cannot
be eliminated, then engineering practices, administrative practices,
work practices, Personal Protective Equipment (PPE), and proper
regarding cranes will be implemented. These measures will be
to minimize those hazards to ensure the safety of employees and the
5.0 General Responsibilities
It is the responsibility of each manager,
supervisor, and employee to ensure implementation of NCDENR's safety
on Cranes. It is also the responsibility of each NCDENR employee to
immediately any unsafe condition to his or her supervisor. Specific
are found in Section 6.3.
This section provides applicable definitions,
general provisions, and identifies specific responsibilities required
NCDENR's safety policy on Cranes.
Accessory- An assembly of parts which
to the overall function and usefulness of a machine.
Appointed- Assigned employee with specific responsibilities by the employer or the employer's representative.
Angle Indicator- An accessory which measures the angle of the boom to the horizontal.
Axis of Rotation- The vertical axis around which the crane superstructure rotates.
Axle- The shaft or spindle with which or about which a wheel rotates. On truck and wheel mounted cranes it refers to an automotive type of axle assembly including housings, gearing, differential, bearings, and mounting appurtenances.
Axle (Bogie)- Two or more automotive type axles mounted in tandem in a frame which divide the load between the axles and permit vertical oscillation of the wheels.
Base-The traveling base or carrier on which the rotating superstructure is mounted such as a car, truck, crawlers, or wheel platforms.
Boom- A member hinged to the front of the rotating superstructure with the outer end supported by ropes leading to a gantry or A-frame and used for supporting the hoisting tackle.
Boom Angle- The angle between the longitudinal centerline of the boom and the horizontal. The boom longitude centerline is a straight line between the boom foot pin (heel pin) centerline and boom point sheave pin centerline.
Boom Hoist- A hoist drum and rope reeving system used to raise and lower the boom. The rope system may be all live reeving or a combination of live reeving and pendants.
Boom Stop- A device used to limit the angle of the boom at the highest position.
Brake- A device used for retarding or stopping motion by friction or power means.
Cab- A housing which covers the rotating superstructure machinery and/or operator's station. On crane trucks a separate cab covers the driver's station.
Clutch A friction, electromagnetic, hydraulic, pneumatic, or positive mechanical device for engagement or disengagement of power.
Counterweight- A weight used to supplement the weight of the machine in providing stability for lifting working loads.
Designated- Selected or assigned by the employer or the employer's representative as being qualified to perform specific duties.
Drum- The cylindrical members around which ropes are wound for raising and lowering the load or boom.
Dynamic Loading- A load introduced into the machine or its components by forces in motion.
Gantry Crane-Overhead- a crane similar to an overhead crane except that the bridge for carrying the trolley or trolleys is rigidly supported on two or more legs running on fixed rails or other runway.
Gantry Crane-(A-Frame)-A structural frame extending above the superstructure to which the boom support ropes are reeved.
Jib- An extension attached to the boom point to provide added boom length for lifting specific loads. The jib may be in line with the boom or offset to various angles.
Load (Working Load)- The external load in pounds applied to the crane including the weight of load-attaching equipment such as load blocks, shackles, and slings.
Load Ratings- Load ratings are the manufacturer's load capacity in pounds.
Outriggers- Extendible or fixed metal arms, attached to the mounting base, which rest on supports at the outer ends.
Rail Clamp- A tong-like metal device, mounted on a locomotive crane car, which can be connected to the track.
Reeving- A rope system in which the rope travels around drums and sheaves.
Rope- A wire rope unless otherwise specified.
Side Loading- A load applied at an angle to the vertical plane of the boom.
Standby Crane- A crane which is not in regular service but which is used occasionally or intermittently as required.
Standing (Guy) Rope- A supporting rope which maintains a constant distance between the points of attachment to the two components connected by the rope.
Structural Competence- The ability of the machine and its components to withstand the stresses imposed by applied loads.
Superstructure- The rotating upper frame structure of the machine and the operating machinery mounted thereon.
Swing- The rotation of the superstructure for movement of loads in a horizontal direction about the axis of rotation. The machinery involved in providing rotation of the superstructure.
Tackle- An assembly of ropes and sheaves arranged for hoisting and pulling.
Transit- The moving or transporting of a crane from one location to another.
Wheelbase- The distance between centers of front and rear axles. For a multiple axle assembly the axle center for wheelbase measurement is taken as the midpoint of the assembly.
Whipline- A separate hoist rope system of lighter load capacity and higher speed than provided by the main hoist.
Winch Head- A power driven spool for handling of loads by means of friction between fiber or wire rope and spool.
6.2 General Provisions
This section details the provisions of this safety policy with each provision discussed in a separate subsection. These provisions are:
Crane operators must be well trained and licensed
by NCDENR because cranes have become more sophisticated and complex.
NCDENR's licensing program for crane operators shall contain:
There are a variety of cranes used within NCDENR, and located on worksites where DENR employees conduct operations. The cranes are used in a variety of settings, indoor and outdoor, from construction activities to overhead cranes. The typical cranes used in NCDENR are:
|Figures 1, 2, 3 and 4 are
illustrations of some of the crane types either used in NCDENR, or on
worksites where DENR employees perform jobtasks.
Appendix A notes specific operating practices for cranes used in NCDENR.
|Figure 3 Wheel Mounted Crane||Figure 4 Double Sided Gantry Crane|
There are inherent hazards associated with crane operations. Therefore, being aware of these hazards is the first step in minimizing these hazards and in promoting a safe working environment. The most common hazards associated with crane use are:
Crane accidents can be prevented if considerations are given to safe use and operation of the crane. The primary components of crane safety are:
Refer to Section 6.2.1 for details on the competency and qualifications requirements for NCDENR crane operators.
Hazard prevention requirements include:
Appendix C presents further details on hazard prevention requirements for crane safety.
6.3 Specific Responsibilities
Managers are responsible for ensuring
adequate funds are available for the purchase of proper equipment,
and training for crane operators and employees associated with crane
Managers will also be responsible for identifying the employees affected by this safety policy.
Manager will obtain and coordinate the required training for the affected employees. Manager will also ensure compliance with this safety policy through their auditing process.
Managers shall be responsible for ensuring all cranes operators are properly trained.
Supervisors will not allow any employee who has
received the required training perform any of the tasks or activities
with this safety policy.
Supervisors will communicate appropriate needs to managers and/or other supervisors.
Supervisors will ensure that employees are provided with PPE as necessary for their job.
Supervisors will ensure the safe operation of cranes. Additionally, they will ensure that all equipment, wire ropes, slings, and other related accessories are in good working condition. If any indication of damaged equipment is present, the equipment will be removed from service and repaired before operations begin.
Employees who are involved in crane operations
ensure that all safety procedures are followed. Operators will ensure
operating procedures are followed. No load will be moved until all
have been taken to ensure that the load can be lifted, moved, and
safely. Each employee is responsible to bring hazards to the attention
of his or her supervisor for correction as soon as the hazard is
Employees will ensure that all PPE is worn properly for the specific hazard involved and that all equipment is in good working order. Refer to SP # 1910.135, Personal Protective Equipment, for additional details.
6.3.4 Safety Risk Management
Safety Risk Management will provide assistance to
managers, supervisors, or others as necessary on any matter concerning
this safety policy. Safety Risk Management will assist in locating any
required training. (To ensure effective implementation of this safety
policy, Division/Office/Program Safety Consultants and Safety Officers
shall be responsible to provide consultative, training and audit
assistance on Crane issues for their Division/Office/Program.)
will also work with Division of Purchase and Services to ensure that
newly purchased equipment complies with safety regulations.
6.3.5 Division of Purchase and Services
Division of Purchase and Services shall ensure
that cranes and crane equipment purchased through their oversight
have been reviewed for safety issues by the Division/Office/Program's
New Equipment Safety Review Subcommittee or the staff Safety
Consultant, or Safety Officer prior to any new purchase
APPENDIX : A Specific Operating Practices
The operator shall not engage in any practice
will divert his attention while actually engaged in operating the crane.
When he or she is physically or mentally unfit, then the operator shall not engage in the operation of this equipment.
The operator shall respond to signals only from the appointed signal person, but shall obey a stop signal at any time, no matter who gives it.
The operator shall be responsible for those operations under his direct control. Whenever safety is in question, the operator shall have the authority to stop and refuse to handle loads until safety has been assured.
No load is to be moved until the swing path and the landing site have been assured to be safe.
If a warning signal is furnished, it shall be sounded each time before traveling and intermittently during travel, particularly when approaching workmen.
Before leaving his crane unattended, the operator shall:
If power fails during operation, the operator shall:
The operator shall familiarize him or herself with the equipment and its proper care. If adjustments or repairs are necessary, or any defects are known, he or she shall report the same promptly to the appointed person and upon changing shifts shall also notify the next operator of the defects.
All controls shall be tested by the operator at the start of a new shift. If any controls do not operate properly, they shall be adjusted or repaired before operations are begun.
Booms which are being assembled or disassembled on the ground with or without support of the boom harness should be securely blocked to prevent dropping of the boom and boom sections.
The following procedures will be observed when moving loads:
Appendix B: Hazards Common to Cranes
contact is the inadvertent contact of any metal part of a crane with a
Most powerline contacts occur when a crane is moving materials adjacent to or under energized powerlines and the hoist line or boom touches a powerline. Contact also frequently occurs during pick-and-carry operations when loads are being transported under energized powerlines.
Sometimes the person who is electrocuted is touching the crane or getting on or off of it when the hoist line or boom inadvertently comes into contact with an energized powerline.
The best hazard prevention method to avoid such an occurrence is to position the crane to keep a 10-foot clearance so the boom or hoist line cannot reach the powerlines.
Powerline contact usually occurs because no one considered the need for specific hazard prevention measures to avoid using cranes near powerlines. The key to avoiding powerline contact is prejob safety planning. Planning is one of the greatest accident deterrents available in the workplace.
A single individual should have overall supervision and coordination of the project and must initiate a positive direction to assure that prejob safety planning is done before any cranes arrive at the worksite.
It is extremely difficult for a crane operator to:
Overloading occurs when the rated capacity of a crane is exceeded while a load is being lifted and maneuvered, resulting in upset or structural failure. Overloading also occurs when poorly trained personnel are allowed to operate cranes. The operator must always know the weight of the load.
Cranes easily upset from overloading. On some models, the weight of a boom without a load can create an imbalance and cause some high-reach hydraulic cranes to upset when the boom is positioned at a low angle. This has occurred even with outriggers extended.
The variables that affect lifting capacity include:
All of these variables create conditions that lead to operators inadvertently exceeding the rated capacity, tipping the load, and upsetting the crane. The variables may also lead to structural failure of the crane.
With the advent of solid-state micro-processing electronics, load-measuring systems evolved. Such systems can sense the actual load boom angle and length, warn the operator as rated capacity is approached, and stop further movement. Load-measuring systems automatically prevent exceeding the rated capacity at any boom angle, length, or radius. Today, most U.S. crane manufacturers are promoting the sale of load-measuring systems as standard equipment on new cranes. There are after-market suppliers of these devices for older model cranes.
For years, the only control to avoid upset from overload has been reliance upon an operator's performance and the use of load charts.
Optimally, formal training shall be provided for all crane operators to ensure a working knowledge of crane load charts. If an on-the-job training program is used, it must be documented that the trainer is qualified to instruct and has completed a formal crane training course, such as the Crane Institute of America or similar course.
Failure to Use Outriggers;
Ground and Structure Failure
Crane upset can occur when an operator does not extend the outrigger or when a crane is positioned on soft ground.
Many cranes upset because the use of outriggers is left to the discretion of the operator. For example, sometimes an operator cannot extend the outriggers because of insufficient space or outrigger pads may be too small to support the crane even on hard ground. However, the use of outriggers is not voluntary. Load capacity charts are based either on the use of fully extended outriggers or on "rubber" for rubber-tired cranes. If outriggers cannot be fully extended, then capacities in the on-rubber chart must be used. Outriggers have collapsed because they were overloaded, defective, or located on inadequate foundation.
Determining the load weights is generally viewed as the responsibility of the site supervisor who must inform the operator before the lift is made. The operator must still be able to determine or estimate load weights, to evaluate and verify the weight provided. Based on the load weight, the operator knows if it is necessary to use outriggers.
The surest way to avoid an accident is to make the machine inoperable until the operator activates necessary safeguards. This could include limit switches to prevent boom movement until outriggers are extended and in place to avert upset.
Soil failure occurs because the ground is too soft or the outrigger pads are not big enough. When poor soil is encountered, or the outriggers have inadequate floats or pads, well designed blocking or cribbing is needed under the outriggers.
Two-blocking occurs when the hoist block or hook assembly comes into contact with the boom tip, causing the hoist line to break and the hook and load to fall, endangering workers below. Two-blocking also occurs because the crane operator is often visually overtaxed. He or she is unable to watch the load and headache ball or hook simultaneously.
Both latticework and hydraulic boom cranes are prone to two-blocking. When two-blocking occurs on latticework booms, the hoist line picks up the weight of the boom and lets the pendant guys go slack. When a hoist line two-blocks, it assumes the weight of the boom and relieves the pin-up guys of the load. The weight of the load plus the weight of the boom on a latticework boom (when combined with a little extra stress when lifting a load) can cause the hoist line to break if two-blocking occurs.
The power of the hydraulic rams that extend hydraulic booms is often sufficient to break the hoist line if the line two-blocks.
In many circumstances, both latticework and hydraulic boom cranes will two-block when the hook is near the tip and the boom is lowered.
OSHA now requires an anti-two-blocking device or a two-block damage prevention feature where cranes are used to hoist personnel.
There are several ways to prevent two-blocking:
A pinch point is created by the narrow clearance between the rotating superstructure (cab) of a crane and the stationery carrier frame. This narrow clearance is referred to as the danger zone.
The swing area of the crane cab and counterweight must be barricaded against entry into the danger zone.
The removal of water jugs, tool boxes, and rigging materials from crane cabs would reduce the incentive to enter the danger zone.
The installation of rear view mirrors for the crane operator provides an added safeguard so the operator can see into the turning area of the cab and counterweight.
Obstruction of Vision
Safe use of a crane is compromised when the vision of an operator, rigger, or signaler is blocked and employees cannot see what the others are doing.
There are two general categories for obstructions to operators' vision:
The crane size alone limits the operator's range of vision and creates many blind spots, preventing the rigger, signaler, oiler, and others affected by the crane's movement from having direct eye contact with the crane operator.
To overcome the hazard of blind spots while loads are being lifted, the use of radios and telephones is much more effective than relying upon several signalers to relay messages by line of sight.
The use of automatic travel alarms is an effective way to warn those in the immediate vicinity of crane travel movement in pick-and-carry functions.
Travel Upset in Mobile
Cranes (Rough Terrain and Wheel-Mounted Telescoping Boom)
Because of a high center of gravity, a mobile hydraulic crane can easily upset and crush the operator between the boom and the ground.
This type of crane is easily overturned on road shoulders or other embankments during travel from one location to another.
The best preventive measure for operator safety is the installation of a crush resistant cab and seatbelt. In the event of a travel upset, the operator would be protected.
Boom Disassembly on
If a boom is not blocked, improper disassembly can cause it to collapse upon those who are removing pins under the boom while the boom is suspended.
Latticework booms are disassembled for shortening, lengthening, or transporting. Boom collapse occurs on truck- or crawler-mounted cranes when the boom is lowered to a horizontal position and suspended from the boom tip with pendant guys, but the boom is not blocked. If the lower pins connecting boom sections are knocked out, the boom can collapse upon workers who are under the boom, resulting in death or serious injuries. Preventive measures during latticework boom disassembly include:
Most crane accidents could have been easily prevented if the safe use of cranes had been incorporated at the preconstruction planning meeting. The planning stage meeting is the best time to address hazard avoidance. Planning before actual crane operations begin can eliminate major craning hazards from the jobsite and make operations more efficient.
Job Hazard Analysis
Before actual craning operations are begun at the jobsite, a specific job hazard analysis should be conducted to ensure that preconstruction planning is adequate. When prejob planning has been neglected, this on-site job hazard analysis is necessary to ensure that craning operations can be done safely.
Standard signals to the operator shall be in accordance with the ANSI standard, unless voice communication equipment (telephone, radio, or equivalent ) is used. Signals shall be discernible or audible at all times. No response shall be made unless signals are clearly understood.
Hand signals shall be in accordance with the ANSI standard for crane hand signals and shall be posted conspicuously. (
Special signals shall be agreed on in advance by the operator and the signal person and should not be in conflict with standard signals. These special signals are for operations not covered by the hand signals or for special conditions that occur from time to time.
If it is necessary to give instructions to the operator other than provided by the established signal system, the crane motions shall be stopped.
Modes of communication must be agreed upon in preconstruction planning and in the job hazard analysis.
Lifting Capabilities and Load
During preconstruction planning, lifting requirements should be analyzed by an engineer competent to establish whether the crane to be used has adequate lifting capability. The job hazard analysis should verify that the crane to be used has sufficient boom length for the lift.
All cranes will be marked with the load ratings and loads will not exceed this amount. A load rating chart will be affixed inside the cab of each crane in sight of the operator. Percentage of loads causing tipping are indicated by crane type and design, and maximum limits will not be exceeded. Figure 1
The requirements for slings to support loads are well defined in OSHA Standards 29 CFR 1910.184 and the requirements for rigging equipment are defined in 29 CFR 1926.251.
Loads will be moved using slings or other approved devices, not by wrapping the rope around the load.
Controlling and Holding the
The use of tag lines to control movement of the load is very important. Normally, when a load is being hoisted, the lay or twist in wire rope causes rotation when the load becomes suspended. OSHA Standard 29 CFR 1910.180(h)(3)(xvi) states: "A tag or restraint line shall be used when rotation of the load is hazardous."
At no time will the operator be allowed to leave the controls while a load is suspended. Employees will be instructed to stay clear and not to pass under suspended loads.
Ballast or Counterweights
Cranes will not be operated without the full amount of ballast or counterweight in place as specified by the manufacturer, unless the load is significantly lighter than the recommended maximum weight.
Firm footing, uniformly level to within one percent (1%) should be provided. Where such footing is not otherwise supplied, it should be provided by substantial timbers, cribbing, or other structural members sufficient to distribute the load so as not to exceed the safe bearing capacity of the underlying material.
Rope Inspection and Wire Rope
All ropes will be inspected for damage each month. Any rope found to be damaged or altered due to stress will be closely monitored for the following warning signs:
It is very important to comply with the crane manufacturer's recommendations for the type of wire rope to be used for various hoist lines or pendants.
New and existing cranes will be inspected each day prior to use. In addition, all cranes will be inspected after any load is dropped or any failure in equipment occurs.
Frequent inspections will be performed on a monthly basis. This inspection will include the following items:
Crane inspections will be performed on cranes that have not been used or are idle or used as standby cranes under the frequent crane inspection guidelines.
A notice of the current annual inspection should be posted in the crane. Cranes that cannot be certified must be removed from service until all necessary repairs are made and the equipment is reinspected.
Inspections will be performed by the supervisor or the designated employee or operator and maintained on hand for a period of three years. These records will include the equipment inspected and the date and signature of the individual who performed the inspection.
Certification records which include the date of inspection, the signature of the person who performed the inspection, and the serial number or other identifier of the crane which was inspected shall be made monthly on critical items in use such as brakes, crane hooks, and ropes.
The following procedures will be observed when transporting cranes from location to location:
Cranes require on-going service and preventive maintenance. Preventive maintenance programs should be documented according to the crane manufacturer's recommendations.