Struck-by Hazard Protective Measures

Heavy Equipment

Cement slab being lifted by a crane.
If the rigging used to lift this cement slab wasn't properly secured, what do you think could happen?

Properly securing any load with appropriate rigging is crucial to any lifting being done by machinery on the job-site. If the rigging fails, the results can cause serious injury and even death. Before any load is lifted all components of the rigging hardware should be evaluated to ensure they can withstand the forces of the load. There are also many other circumstances that you will need to be aware of when working around heavy equipment. Following the safe work practices listed below will greatly enhance your ability to remain safe while working around heavy equipment.

  • Guard all exposed gears, rotating shafts, pulleys, sprockets or other moving parts to prevent contact with employees.
  • Stay away from heavy equipment when it’s operating – In fact, be alert to the location of all heavy equipment whether in use or not.
  • Be aware of the swing radius of cranes and backhoes and do not enter that zone.
  • Inspect all rigging equipment prior to each lift, this should include all slings, chains, ropes, and like materials used to support and lift materials.
  • Remove from service any defective equipment immediately.
  • Inspect all hooks, clamps, and other lifting accessories for their rated load.
  • Stay clear of lifted loads and never work under a suspended load.
  • The person responsible for signaling the crane operator needs to stay in visual contact with the operator and is trained to use the correct signals.
  • Beware of unbalanced loads.
  • Workers should confirm and receive acknowledgment from the heavy equipment operator that they are visible.
  • Drive equipment [or vehicles] on grades or roadways that are safely constructed and maintained.
  • Make sure all workers and other personnel are in the clear before using dumping or lifting devices.
  • Lower or block bulldozer and scraper blades, end loader buckets, dump bodies, etc., when not in use, and leave all controls in neutral position.
  • Haulage vehicles that are loaded by cranes, power shovels, loaders etc., must have a cab shield or canopy that protects the driver from falling materials.
  • Do not exceed a vehicle's rated load or lift capacity.
  • Do not carry personnel unless there is a safe place to ride.

1. What should be done with heavy equipment blades, buckets, and dump bodies when not in use?

a. Keep all equipment properly engaged and tagged
b. Lockout and tagout the equipment controls
c. Block and lower, and leave controls in neutral position
d. Keep blades raised, buckets lowered, and leave in off position

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Heavy Equipment – Cranes, Excavators, and more (Continued)

A cranes outrigging supported in muddy conditions.
Does your employer need to ensure the ground is sufficiently level and firm to support the work of the crane?

There are also many things your employer must do to ensure your safety around heavy equipment as well, such as:

  • determining whether the ground is sufficiently level and firm to support the anticipated weight of hoisting equipment and associated loads;
  • assessing hazards within the work zone that would affect the safe operation of hoisting equipment such as, power lines and objects or personnel that would be within the swing radius of the hoisting equipment;
  • erecting barriers to mark the area covered by the rotating superstructure to warn workers of the danger zone;
  • ensuring equipment is in safe operating condition via required inspections;
  • complying with all manufacturer procedures regarding proper operational functions of equipment, including its use with attachments;
  • ensuring safe attachment of rigging devices such as shackles, hooks, eyebolts, spreader beams and slings, wedge socket and wire rope clips;
  • providing seat belts when required;
  • ensuring roadways and grades are maintained to accommodate the safe movement of equipment and vehicles; and
  • ensuring all earthmoving/compacting equipment with obstructed view does not operate in reverse gear unless the equipment has a reverse signal alarm, or a worker has been designated to signal when it is safe.

To learn more about cranes and rigging safety please click here. For more comprehensive information please consider reviewing course 820 Crane and Derrick Safety I, and 821 Crane and Derrick Safety II.

2. Proper equipment operation should be in compliance with _____.

a. industry standards
b. manufacturer procedures
c. OSHA instructions
d. operator best practices

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Motor Vehicles – Trucks, Cars, and More

Workers often deal with low lighting, low visibility, inclement weather, multiple vehicles, and numerous distractions at worksites. Moving construction vehicles and passing motor vehicle traffic can both cause problems for construction workers. Vehicle safety practices must be observed at construction sites to limit worker exposure to struck-by hazards such as struck-by swinging backhoes, struck-by falling/overturning vehicles, and struck-by trucks or cars.

To avoid these types of hazards, workers should:

  • wear seat belts when provided;
  • check vehicles before each shift to assure that all parts and accessories are in safe operating condition;
  • do not drive a vehicle in reverse gear with an obstructed rear view, unless it has an audible reverse alarm, or another worker signals that it is safe;
  • set parking brakes when vehicles and equipment are parked, and chock the wheels if they are on an incline;
  • all vehicles must have adequate braking systems and other safety devices;
  • use traffic signs, barricades or flaggers when construction takes place near public roadways; and
  • workers must be highly visible in all levels of light. Warning clothing, such as red or orange vests, are required, and if worn for night work, must be of reflective material.

3. If a vehicle has an obstructed rear view, what must the operator have in order to back up the vehicle?

a. Audible reverse alarm, or another worker to signal it's safe
b. A designated flagger or signal-person to direct traffic
c. A jury-rigged backup mirror, or visible signal
d. A hand-held high-lumen flashlight, or audible alarm

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Motor Vehicles – Trucks, Cars, and More (Continued)

Warning signs in a traffic zone.
Your employer is required to ensure the necessary warning signs are placed along the road.

When working on or near any construction zone:

  • wear high-visibility reflective clothing;
  • do not put yourself at risk of being struck by a vehicle and do not get caught in a situation where there's no escape route;
  • do not direct traffic unless you are the flagger;
  • flaggers must be visible by both motorists and equipment operators;
  • check that necessary warning signs are posted;
  • never cross the path of a backing vehicle;
  • if equipment doesn't have a reverse signal alarm loud enough to be heard against the surrounding noise level, and the operator has an obstructed view to the rear, the employer will designate a worker to signal when it’s safe to back up; and
  • follow "Exit" and "Entry" worksite traffic plan.

Flaggers and other workers on foot are at greater risk of exposure to being struck; therefore, they must be visible by both motorists and equipment operators.

Your employer is required to:

  • conduct a hazard assessment of the worksite using the job-site coordinator (supervisor or foreman) who should:
    • make a thorough assessment of potential worksite safety hazards,
    • plan for work being conducted in close proximity to a public road or highway and for the safe handling of intermittent roadway traffic stoppages, such as a truck entering a roadway, and
    • plan the entry and exit to and from the worksite to reduce exposure to traffic;
  • post-construction areas with legible traffic signs at points of hazard;
  • erect barricades that conform to the MUTCD;
  • place necessary warning signs along the road; and
  • all workers on site should have a safety and operations orientation.

If you're interested in learning more about work zone traffic safety, please review course 612 Work Zone Traffic Safety.

4. If a vehicle does not have a reverse signal alarm and the operator has an obstructed view to the rear, the employer must _____.

a. wear high-visibility clothing
b. take care when crossing the path of a backing vehicle
c. provide illuminated signs for drivers
d. designate a worker to signal safe backing

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General Safe Work Practices

As an employee, you are your own best advocate for keeping yourself safe. Below is a list of safe work practices to help you.

When working with compressed air:

  • reduce air pressure to 30 psi if used for cleaning, and use only with appropriate guarding and proper protective equipment; and
  • never clean clothing with compressed air.

When working with hand tools:

  • do not use tools with loose, cracked or splintered handles; and
  • do not use impact tools with mushroomed heads.

When working with machines, such as jack hammers, pavement saws:

  • be sure to be trained on safe operation of machinery;
  • inspect machinery and ensure all guards are in place and in working order;
  • protect feet, eyes, ears and hands; and
  • wear hearing protection.

When performing overhead work:

  • secure all tools and materials;
  • use toeboards, screens, guardrails and debris nets;
  • barricade the area and post signs; and
  • be sure materials stored in buildings under construction are placed further than 6 feet of hoist way/floor openings and more than 10 feet from an exterior wall.

5. How far from hoist ways/floor openings must materials be stored?

a. Two feet or farther
b. At least 6 feet
c. No closer than 4 feet
d. Between 4 and 6 feet

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General Safe Work Practices (Continued)

When working with power-actuated tools you must be trained and licensed to operate them if required.

When working with power tools, such as saws, drills, and grinders:

  • be sure to be trained on how to safely use the power tool;
  • inspect tools before each use;
  • wear safety goggles;
  • operate according to manufacturer’s instructions; and
  • ensure all required guards are in place.

When pushing or pulling objects that may become airborne:

  • stack and secure materials to prevent sliding, falling or collapse;
  • keep work areas clear; and
  • secure material against wind gusts.

6. Which of the following tools require workers to be trained and licensed, if required?

a. Hydraulic tools
b. Electrical tools
c. Pneumatic tools
d. Powder-actuated tools

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General Safe Work Practices (Continued)

Your employer is responsible for ensuring:

  • all hand tools are maintained in good condition;
  • the use of unsafe hand tools is not permitted (i.e., no sprung jaws on wrenches, no mushroomed heads, no splinters or cracks in wooden handles, no loose parts/heads of tools);
  • saws are equipped with guards and have a constant pressure switch that will shut off the power when the pressure is released;
  • safety guards are on all abrasive wheel bench and stand grinders;
  • all powder-actuated tools are tested daily before use and all defects discovered before or during use are corrected;
  • powder-actuated tools are not loaded until immediately before use and loaded tools are not left unattended;
  • compressed air used for cleaning purposes is reduced to less than 30 pounds per square inch (psi) and provide effective chip guarding and PPE;
  • all materials stored in tiers are secured to prevent sliding, falling, or collapsing; and
  • toeboards are erected along the edge of overhead walking/working surfaces.

7. Compressed air used for cleaning purposes is must be reduced _____.

a. to no more than 50 pounds per square inch (psi)
b. to less than 30 pounds per square inch (psi)
c. prior to first use during the workshift
d. to no more than a 20% oxygen level

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Personal Protective Equipment (PPE)

Helmet, gloves, and safety glasses
Personal Protective Equipment must be worn and used in a manner that will make full use of its protective qualities.

Personal Protective Equipment must be worn and used in a manner that will make full use of its protective qualities. Personal protective equipment used incorrectly potentially exposes an employee to hazards, which defeats the reason for using PPE. To review a "PPE for Workers Checklist" click here.

Eye and face protection should be used based on anticipated hazards. Safety glasses or goggles should be worn any time work operations present an eye hazard. For example, safety glasses or goggles should be worn during welding, cutting, grinding, nailing (or when working with concrete and/or harmful chemicals or when exposed to flying particles).

Head protection (i.e., hard hats) should be used where there is a potential for objects falling from above, and bumps to the head from fixed objects. Hard hats should be routinely inspected for dents, cracks or deterioration. Replace your hard hat after a heavy blow and ensure it is maintained and in good condition.

When worn alone, face shields do not protect employees from impact hazards. Workers should use face shields in combination with safety spectacles or goggles, even in the absence of dust or potential splashes, for additional protection beyond that offered by spectacles or goggles alone.

Your employer must do the following:

  • Pay for PPE as required by OSHA.
  • Provide and require the use of appropriate PPE in all operations where there is an exposure to hazardous conditions.
  • Ensure the adequacy of PPE including proper maintenance and sanitation.
  • Provide head protection (e.g., hard hats, helmets) whenever there is possible danger of head injuries from impact, flying or falling objects.
  • Provide eye and face protection when machines or operations present eye or face injury.
  • Provide workers involved in welding operations with filter lenses or plates of proper shade number.
  • Ensure eye, face, and head protective equipment meets ANSI requirements.

8. When worn alone, using face shields _____ employees from impact hazards.

a. are better than goggles in protecting
b. will adequately protect
c. will not protect
d. is the best choice to protect

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To help protect you from struck-by hazards your employer must:

  • Train workers in the work zone to recognize hazards associated with the use of the equipment and any related duties that they are assigned to perform.
  • Ensure crane operators are qualified or certified according to OSHA standards.
  • Ensure signal person meets qualification requirements according to OSHA standards.
  • Instruct workers in the recognition and avoidance of unsafe conditions and the regulations applicable to his/her work environment to control or eliminate any hazards or other exposure to illness or injury.
  • Ensure qualified operators and riggers have been trained on rigging safety, such as:
    • the weight [of load] the rigging is expected to support
    • the capacity of the strength of the rigging (type and method of use)
    • how to retain the load – know which hitches work best for certain types of loads
    • how to control the load – know which hitches provide good load control and where the center of gravity of the load is

9. Employers must train workers in the construction site work zone to _____.

a. enforce the employer's safety rules
b. recognize hazards and their related duties
c. control the movement of employees at all times
d. anticipate and report suspicious behaviors

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Optional Exercise: Accident Scenario

Read the accident investigation summary and see what recommendations you might have.

Fall from tilt-up concrete wall
Accident Type: Struck by Collapsing Crane Boom
Weather Conditions: Clear
Type of Company: General Contractor
Size of Work Crew: 9
Union or Non-Union: Union
Competent Safety Monitor on Site: Yes
Safety and Health Program in Effect: Yes
Was the Worksite Inspected Regularly: Yes
Training and Education Provided: Yes
Employee Job Title: 1. Iron Worker 2. Management Trainee
Age & Sex: 1. Ironworker-35; male 2. Management Trainee-26; male
Time on the Job: 1 Hour
Time on the task: 1 Hour

Description of Accident

A crew of ironworkers and a crane operator were unloading a 20-ton steel slab from a low-boy trailer using a 50-ton crawler crane with 90-foot lattice boom. The operator was inexperienced on this crane and did not know the length of the boom. Further, no one had determined the load radius. During lifting, the load moved forward and to the right, placing a twisting force on the boom. The boom twisted under the load, swinging down, under and to the right. Two employees standing 30 feet away apparently saw the boom begin to swing and ran. The boom struck one of the employees - an ironworker - on the head, causing instant death. Wire rope struck the other -- a management trainee -- causing internal injuries. He died two hours later at a local hospital.

What would you recommend?