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Course 808: Focus Four - Struck-By Hazards

Safety guides and audits to make your job as a safety professional easier

Protecting Yourself from Struck-by Hazards

Heavy Equipment – Cranes, Excavators, and more

Employer Responsibilities

There are a number important actions the employer must take to ensure your safety while working around heavy equipment on the worksite.

Click on the buttons below to see the list of employer actions and a summary of an accident.

  • determine if the ground is sufficiently level and firm to support the anticipated weight of hoisting equipment and associated loads;
  • assess 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;
  • erect barriers to mark the area covered by the rotating superstructure to warn workers of the danger zone;
  • ensure equipment is in safe operating condition via required inspections;
  • comply with all manufacturer procedures regarding proper operational functions of equipment, including its use with attachments;
  • ensure safe attachment of rigging devices such as shackles, hooks, eyebolts, spreader beams and slings, wedge socket and wire rope clips;
  • provide seat belts when required;
  • ensure roadways and grades are maintained to accommodate the safe movement of equipment and vehicles; and
  • ensure 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.

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 causing internal injuries. He died two hours later at a local hospital.

What would you recommend?


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.

1. What action should the employer take to protect workers when a crane with a rotating superstructure is operating on the worksite?

a. Secure the load with whatever you happen to have on-site
b. Erect barriers to mark the area covered by the rotating superstructure
c. Ensure barricades located near the crane do not impede the movement of workers
d. Use a spotter when operating in reverse gear

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Heavy Equipment – Cranes, Excavators, etc. (Continued)

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.

Click on the button below to see a list of safe work practices that 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.

2. Each of the following is a required safe work practice when working around heavy equipment EXCEPT _____.

a. Stay clear and do not work under lifted loads
b. Be aware of unbalanced loads
c. Lower or block bulldozer blades when not in use
d. Remove seatbelts so workers can escape during a rollover

Next Section

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

Employer Responsibilities

Prior to the start of a project, the employer and job-site coordinator (supervisor or foreman) should conduct a hazard assessment for potential worksite safety hazards. The employer and job-site coordinator should also:

  • 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
  • conduct operations and safety orientations for all workers on site.

Safe Practices

Workers often deal with safety hazards such as 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 operation safety practices must be observed at construction sites to limit worker exposure to struck-by accidents such as struck-by swinging backhoes, struck-by falling/overturning vehicles, and struck-by trucks or cars.

Click on the buttons below to see a list of safe work practices when operating vehicles.

  • 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.

Click on the buttons below to see a list of safe work practices when working in high hazard work zones.

  • 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.

Click on the buttons to watch a WorkSafeBC video on worksite dangers and a KGW TV video on a flagger accident.

3. Each of the following is required when operating vehicles and/or heavy equipment on construction sites EXCEPT _____.

a. wearing seatbelts
b. an audible reverse alarm
c. rotating strobe lights
d. highly visibility clothing

Next Section

General Safe Work Practices

Employer Responsibilities

Click on the buttons below to see a list of general safe practices for which the employer is responsible for ensuring.

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;
  • only trained workers are allowed to operate powder-actuated tools;
  • 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.

Safe Practices - Compressed Air

As an employee, you are your own best advocate for keeping yourself safe. Click on the button below to see a list of general safe practices when working with compressed air.

When working with compressed air:

  • get trained on the equipment prior to first use;
  • make sure equipment is in good condition and the gauges are accurate;
  • reduce air pressure to 30 psi if used for cleaning equipment, etc.;
  • and use only with appropriate guarding and proper protective equipment; and
  • never clean clothing with compressed air.

Safe Practices: Hand and Power Tools

Click on the buttons below to see a partial list of general safe practices performing work using hand and power tools.

When working with hand and power tools:

  • do not use hand tools with loose, cracked or splintered handles;
  • do not use hand impact tools with mushroomed heads; and
  • recondition or replace deformed hand tools such as chisels, punches, etc.
  • replace broken, worn, or otherwise defective tools immediately;
  • store tools in secure and dry location;
  • be sure to be trained on how to safely use the tool;
  • inspect tools before each use;
  • wear safety goggles, face shields, gloves, and other PPE as necessary;
  • operate according to manufacturer's instructions; and
  • ensure all required guards on power tools are in place.

Click on the buttons below to view several videos on safe practices when working with air compressors and circular saws.

4. Compressed air used for cleaning purposes must be reduced to _____.

a. approximately 14.7 psi
b. less than 30 pounds psi
c. between 20 and 25 psi
d. no more than 40 psi

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General Safe Work Practices (Continued...)

Safe Practices: Powder-Actuated Tools

Click on the buttons below to see a partial list of general safe practices when using powder-actuated tools.

When using powder-actuated tools:

  • 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; and
  • workers must always be trained and, when required, they must be licensed to operate powder-actuated tools.

Overhead Work

Click on the buttons below to see a partial list of general safe practices performing overhead work.

When performing overhead work on construction sites:

  • secure all tools and materials;
  • use guardrails, toeboards, screens, debris nets;
  • barricade the area and post signs; and
  • store materials more than 6 feet away from hoistways/floor openings; and
  • store materials more than 10 feet away from exterior walls.

Airborne Objects

Click on the buttons below to see a partial list of general safe practices performing work handling airborne objects.

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.

You can review OSHA's Small Business Handbook and the Hand and Power Tools Guide for more information on hand and power tool safety.

Click the buttons below to watch two short videos on powder-actuated tools and hoist safety. You can also review the details of an abrasive wheel accident.

Old tools that may need to be replaced.

Description of the accident. A worker was cutting a 6-inch steel water pipe with a gas-powered abrasive wheel when the saw kicked back and struck the worker’s face shield, resulting in a laceration and two fractures of the nose.

What would you recommend?

Below is a list of actions that could be taken to ensure an accident like this does not occur.

  • Wear safety glasses and face shields when working with these tools.
  • Make sure workers using powder-actuated tools have been trained. If not, they are a risk to everyone working nearby.
  • Never place hand or fingers over the front muzzle end of a powder-actuated tool and always hold the tool perpendicular to the work, ensuring the spall guard is in place.
  • Inspect tools to ensure protective guards are in place and in good condition.
  • Perform ring tests of grinding wheels to determine if they are intact.
  • Keep the cord behind the cut to prevent cutting the cord.
  • Never stand in line with the unprotected part of a grinding wheel, stand to the side and out of the plane of rotation during start-up. Always wear safety glasses and full-face shields.
  • Check electric tools for defects, such as missing grounding pins and cracked cases, before using.
  • Always use a GFCI.

5. Be sure materials stored in buildings under construction are placed _____ away from hoistways and floor openings.

a. 4 or more feet
b. more than 10 feet
c. at least 2 feet
d. more than 6 feet

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Personal Protective Equipment (PPE)

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.

Employer Responsibilities

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.

Watch this videos for more information on PPE:

6. When worn alone, face shields do not protect employees from impact hazards. Workers should use face shields with _____.

a. safety spectacles or goggles
b. a half-face respirator
c. tinted type 1 plastic
d. two support straps

Next Section


Safety education is accomplished in three phases: instruction, training, and evaluation to ensure employees have the necessary knowledge, skills, and abilities (KSAs) required to work safe on the job. Employees must instructed on OSHA regulations, company safety policies, programs, procedures, and how to avoid unsafe conditions. They must be trained on how to properly use and maintain tools, equipment, and machinery. Finally, they must be evaluated by a competent person and certified as competent to use equipment and perform procedures.

Employer Responsibilities

Employers are held accountable by OSHA to develop a suitable safety training program. It's important to know that OSHA will ALWAYS inspect the safety training program during an OSHA inspection. Click on the button below to see more specific training responsibilities for which employers are held accountable.

  • 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:
    • know the weight [of load] the rigging is expected to support
    • know the capacity of the strength of the rigging (type and method of use)
    • retain the load – know which hitches work best for certain types of loads
    • control the load – know which hitches provide good load control and where the center of gravity of the load is

See an example of an actual accident and a video by WorkSafeBC on the tragic consequences of an accident while working with power tools.

Fall from tilt-up concrete wall

Description of Accident

Employees were dismantling grain spouts at a grain elevator. Sections of the spout were connected by collars. A ten foot section of a spout weighing 600 pounds was being pulled through a vent hole by a 5-ton winch. As the spout was being pulled through the opening to the outside, the spout became wedged at the point where the collar was to pass through. Several employees used pry bars to free the collar which was under tension. The spout popped out of the vent striking and killing an employee who was standing beside the spout. Employer provided but did not require use of hard hats.

Inspection Results

As a result of its investigation, OSHA issued two citations alleging serious violations. The employee should have been able to recognize that this situation was hazardous. Additionally, the investigation revealed that this employee was not wearing personal protective equipment in this hazardous situation. Had he been wearing a hard hat this death might have been prevented.

What would you recommend?


Employees must be instructed in the recognition and avoidance of unsafe conditions. They must also be instructed in the regulations applicable to the work environment to control or eliminate any hazards or other exposure to illness or injury [29 CFR 1926.21(b)(2)].

For more information on OSHA training requirements see OSHA Pub 2254, Training Requirements in OSHA Standards, and OSHAcademy Course 701, Introduction to OSHA Training.

7. Successful safety education improves each of the following EXCEPT _____.

a. knowledge
b. emotions
c. skills
d. abilities

Check your Work

Read the material in each section to find the correct answer to each quiz question. After answering all the questions, click on the "Check Quiz Answers" button to grade your quiz and see your score. You will receive a message if you forgot to answer one of the questions. After clicking the button, the questions you missed will be listed below. You can correct any missed questions and check your answers again.

Final Exam