The sky above you

Cranes and overhead work can put you in danger. Whether you are a crane operator, site supervisor or general laborer, you must do your part to cut the chances of crane and overhead accidents.

by Ken Busch

Whether you operate a crane, work for a company utilizing cranes, or work for a contractor who places you in proximity of cranes, safety around cranes is very serious business. Often, because so many contractors work so closely on a jobsite, the responsibility for overall crane safety goes undetermined, or at least remains hazy.

What happens when a construction company rents a crane from a third party, then contracts a worker to operate the crane? Which party has safety accountability? Who makes sure the operator has used a crane of this particular size or type? These are questions that must be answered on every jobsite where cranes are used.

The facts on crane accidents are disturbing. Every year, hundreds of workers are killed or injured in crane accidents. They are hurt or killed from the effects of electrocution from contact with overhead power lines, crushing accidents and being struck by objects being moved by the crane.

“In 1999, at least one crane accident occurred each month. Non-crane operator fatalities exceed those of the operators themselves,” says Paul Satti, technical director at the Construction Safety Council.

He warns of attitude problems causing safety issues with cranes. “When a crane is on the job, often there is a ‘let’s just get it done’ attitude. This can be dangerous,” he says. “With cranes, you can’t just make do. Fatalities are not uncommon in crane accidents.”

Satti has been working on a training program for jobsite supervisors who need to manage crane and overhead work safety on jobsites. Lawsuits have set the parameters on accountability for jobsites, and Satti’s crane safety training covers the supervisors’ responsibilities. Specifically, a supervisor should know how to select a crane according to load, farthest reach, soil conditions and height. He hopes that programs like this become the norm.

The Occupational Safety and Health Administration (OSHA) provides guidelines for minimum levels of safety for crane operation. OSHA can cite organizations that willfully violate these guidelines. It defines a violation as one committed with intentional defiance of, or plain indifference to, the requirements of the OSHA regulations.

What’s your responsibility?
Responsibilities for safe crane operation fall across several people on a jobsite:

The owner/contractor: Crane owners and construction firms must ensure crane operators are generally capable and aware of all responsibilities, fully understand the load charts and are familiar with the crane they will be operating. They also have the responsibility of inspection and maintenance as well as training and upgrading programs.

Site supervision: Supervisors are generally responsible for overseeing the safety of the entire construction zone, including cranes. They must also see to it the working area is prepared correctly for a crane, the load weight and radius is correct and the rigging crew is experienced and competent.

Crane operators: Operators should have a recognized certificate or degree, know the machine they are operating, understand the crane’s load chart and be able to inspect and maintain the crane.

Riggers: A qualified rigger must ensure the rigging equipment and materials are in compliance with regulations that affect the procedure.

The rigger must also confirm the load path is clear of people and obstacles. Riggers must follow four rigging rules: 1.) Know the weight of the load the rigging is going to support; 2.) Know the capacity of the rigging hardware; 3.) Retain the load while it is in the air; and 4.) Control the load so that it does not change position while on the hook.

If these basic practices are followed, the rigging work will go safely.

Crane selection
Proper crane selection is key to cutting the chances of a crane accident. When selecting a crane, consider what the heaviest and largest loads will be, the maximum lift height and lift radius needed, the serviceability of the equipment and the conditions of the site. Ask crane experts if you are unsure of jobsite requirements.

Improper selection is only one potential pitfall with crane use, says Satti, “Many jobsite conditions can contribute to a crane accident. Before a crane arrives onsite, check and recheck all conditions, looking for existing and potential hazards.”

The supporting surface, work area and access/usability must be reviewed. On almost all ground conditions, blocking or cribbing is recommended to ensure crane stability.

Improper outrigger use
Over 50 percent of all mobile crane failures and upsets are caused by improper use of outriggers, poor ground conditions and improper blocking beneath outrigger floats.

Although cranes with float pads are small enough for one person to move and position, it’s important to spread the weight of the load with blocking or cribbing to help transport the load without bending or breaking.

Leveling the crane is as important as blocking the crane. An out-of-level crane has reduced lifting capacity. Most load charts require a crane to be within one percent grade of being perfectly level. When this isn’t possible, site supervisors and operators should consult the crane manufacturer’s load charts and identify the load deration needed at that angle.

Electrocution dangers
Electrocution is a deadly hazard associated with crane use. Because the electrocution danger is so great, OSHA mandates: “Before work is done, the employer shall ascertain by inquiry or direct observation, or by instruments, whether any part of an energized electric power circuit, exposed or concealed, is so located that the performance of the work may bring any person, tool, or machine into physical or electric contact with the electric power circuit. The employer shall post and maintain proper warning signs . . . [and] advise employees of the location of such lines . . .”

The OSHA-required power line clearance distance for cranes or any other equipment or material, is 10' for lines 50 kV and less. For lines greater than 50 kV, stay at least 35' away.

Other preventive measures include having the power line de-energized or moved, using barrier protection, installing flagged warning lines and installing protective technologies that warn when the crane is too close to energized lines.

What if a crane comes in contact with a power line? “The crane operator should stay inside the cab and try to remove the crane from contact. All other personnel should keep away from the crane, ropes, and load. If the operator must leave the crane, he or she should jump from the equipment and land with both feet together, then shuffle with very small steps away from the crane,” Satti says.

If an electrocution occurs, under no circumstances should anyone approach or touch the injured person. “Regardless of your emotions, touching or approaching an electrocuted individual will only result in two or more victims instead of one,” says Satti. Approach the victim only when everyone is sure power has been turned off.

Caught-in-between hazards
Hazards of being caught in, compressed, or crushed by crane equipment are as horrifying as electrocution hazards, but can be avoided. Most often, workers are injured or killed by being crushed by the swinging superstructure of the crane. Use barricades to prevent workers from entering crane work zones.

OSHA guidelines say, “Accessible areas within the swing radius of the rear of the rotating superstructure of the crane . . . shall be barricaded in such a manner as to prevent an employee from being struck or crushed by the crane.”

Pinch points are another common cause of injury and death. Also referred to as mesh points, run-on points or entry points, they should be identified with high-visibility warning decals. Pinch points should have guards in place whenever possible.

Cranes are one of the most productive and expensive pieces of equipment on a jobsite.

A hard-working crane is very important to the entire schedule of a project, but can only work hard when it’s operated by a qualified crane operator and respected by all workers on the site within the crane’s reach.

“Because of the sheer magnitude of cranes, they can also be the root of catastrophic accidents. It’s everyone’s responsibility to follow safety guidelines set up by OSHA. Keep safety protocol at the forefront of any project,” says Satti.

Published in the January/February 2002 issue of Contractor Tools and Supplies magazine.

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