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OSHA 30 Construction practice questions

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Question 1Introduction to OSHA

In what year was the Occupational Safety and Health Act signed into law?

  1. 1970 Correct answer.
  2. 1965
  3. 1974
  4. 1981

Explanation

The OSH Act was signed on December 29, 1970, and took effect on April 28, 1971. It created the Occupational Safety and Health Administration within the U.S. Department of Labor.

Question 2Introduction to OSHA

OSHA operates as an agency within which federal department?

  1. Department of Health and Human Services
  2. Department of Labor Correct answer.
  3. Environmental Protection Agency
  4. Department of Commerce

Explanation

The OSH Act is administered by the Secretary of Labor, and OSHA is an agency of the U.S. Department of Labor. NIOSH, by contrast, is part of the public health service structure.

Question 3Introduction to OSHA

What is the common name for the broad requirement found in Section 5(a)(1) of the OSH Act?

  1. The abatement clause
  2. The general duty clause Correct answer.
  3. The compliance clause
  4. The hazard notice clause

Explanation

Section 5(a)(1) requires each employer to furnish a workplace free from recognized hazards that are causing or likely to cause death or serious physical harm. It applies even where no specific standard addresses the condition.

Question 4Introduction to OSHA

An employer must report a work-related fatality to OSHA within how many hours of learning of it?

  1. 24 hours
  2. 12 hours
  3. 8 hours Correct answer.
  4. 4 hours

Explanation

Work-related fatalities must be reported to OSHA within 8 hours. In-patient hospitalizations, amputations, and losses of an eye must be reported within 24 hours.

Question 5Introduction to OSHA

Which part of Title 29 of the Code of Federal Regulations contains OSHA's construction industry standards?

  1. 40 CFR 1926
  2. 29 CFR 1904
  3. 29 CFR 1910
  4. 29 CFR 1926 Correct answer.

Explanation

Part 1926 of Title 29 contains the construction standards, while Part 1910 covers general industry. Employers in construction generally follow Part 1926 unless a specific 1910 standard is incorporated by reference.

Question 6Introduction to OSHA

Under the OSH Act, an employee who believes a workplace condition is unsafe may:

  1. ask a union steward to petition the review commission
  2. file a complaint with OSHA and request an inspection Correct answer.
  3. request a variance from the nearest OSHA area office
  4. file a complaint only after notifying the employer in writing

Explanation

Any employee may file a complaint with OSHA and ask for an inspection, and may request that their name be kept confidential from the employer. No prior notice to the employer is required.

Question 7Introduction to OSHA

A general contractor controls a site where a subcontractor's workers are exposed to an unguarded floor opening created by a different subcontractor. Under OSHA's multi-employer citation policy, who may be cited?

  1. Only the subcontractor that physically created the unguarded opening
  2. Only the subcontractor whose own employees were directly exposed to the opening
  3. The controlling contractor and the employers that created or exposed workers to the hazard Correct answer.
  4. No employer, because the opening existed for only part of a shift

Explanation

OSHA's multi-employer policy allows citations to creating, exposing, correcting, and controlling employers. A controlling contractor that has general supervisory authority and could reasonably detect and correct the hazard may be cited along with the creating and exposing employers.

Question 8Introduction to OSHA

How long does an employee have to file a discrimination complaint with OSHA under Section 11(c) of the OSH Act?

  1. 15 working days
  2. 6 months
  3. 60 days
  4. 30 days Correct answer.

Explanation

Section 11(c) prohibits retaliation for exercising rights such as filing a complaint or refusing imminently dangerous work, and a complaint must be filed within 30 days of the adverse action.

Question 9Introduction to OSHA

A state plan approved by OSHA must be:

  1. limited to employers with federal contracts only
  2. identical in wording to the federal standards, with no variations
  3. at least as effective as the federal program Correct answer.
  4. reapproved by the Secretary of Labor every two years

Explanation

A state may run its own program only if OSHA approves it as at least as effective as the federal program. State standards may differ in wording and may cover additional hazards.

Question 10Introduction to OSHA

The OSHA Form 300A Summary of Work-Related Injuries and Illnesses must be posted:

  1. by March 1 and remain posted for 30 days
  2. from February 1 through April 30 Correct answer.
  3. within 7 days after the end of the calendar year
  4. by December 31 and remain posted all year

Explanation

Covered employers must post the 300A summary in a conspicuous place from February 1 through April 30 of the year following the recording year. The summary shows totals only, not individual case details.

Question 11Introduction to OSHA

An employer must report a work-related in-patient hospitalization of a single employee to OSHA within:

  1. 24 hours Correct answer.
  2. 8 hours
  3. 72 hours
  4. 15 working days

Explanation

In-patient hospitalizations, amputations, and losses of an eye must be reported within 24 hours of the employer learning of them. Fatalities carry the shorter 8-hour deadline.

Question 12Introduction to OSHA

Which situation receives OSHA's highest inspection priority?

  1. An employee complaint submitted in writing
  2. Imminent danger situations Correct answer.
  3. A fatality that occurred three weeks ago
  4. A programmed inspection of a high-hazard industry

Explanation

OSHA ranks imminent danger first because workers face a risk of death or serious harm before the hazard can be abated through normal procedures. Fatalities and catastrophes come next, followed by complaints and referrals, then programmed inspections.

Question 13Introduction to OSHA

During an OSHA inspection, the authorized employee representative's role in the walkaround is to:

  1. accompany the compliance officer on the walkaround Correct answer.
  2. decide which violations will be cited by the agency
  3. negotiate penalty amounts with the compliance officer
  4. speak for the employer at the closing conference

Explanation

An employee selected by the workforce may accompany the compliance officer during the physical inspection and may point out hazards and speak with other workers. The employer also has a representative present, but the two roles are distinct.

Question 14Introduction to OSHA

A violation is classified as serious when there is:

  1. lost workdays exceeding five for the affected employee
  2. a prior citation for the same condition at the same site
  3. a written complaint signed by two employees
  4. a substantial probability of death or serious harm Correct answer.

Explanation

A serious violation exists where there is a substantial probability that death or serious physical harm could result and the employer knew or should have known of the hazard. Actual injury is not required.

Question 15Introduction to OSHA

Which statement describes OSHA's On-site Consultation Program?

  1. An enforcement program that issues citations and collects penalties
  2. The state-plan substitute for programmed federal inspections
  3. Free assistance that proposes no penalties when hazards are corrected Correct answer.
  4. A program restricted to employers with ten or fewer workers

Explanation

The consultation program offers free, confidential advice to small and mid-sized employers and does not propose penalties for hazards the employer corrects. It is separate from enforcement and must refer imminent danger situations to OSHA.

Question 16Introduction to OSHA

Under OSHA's access to employee exposure and medical records standard, an employer must provide an employee with access to their medical records within:

  1. 5 working days
  2. 72 hours
  3. 15 working days Correct answer.
  4. 30 calendar days

Explanation

Employees must be given access to their exposure and medical records within 15 working days of a request. Exposure records must be provided without regard to whether the employee was directly exposed.

Question 17Introduction to OSHA

To prove a general duty clause violation, OSHA must show that:

  1. actual injury resulted from the unsafe condition
  2. a specific standard covered the exact condition
  3. a recognized serious hazard could feasibly be abated Correct answer.
  4. the employer had a prior citation for the same hazard

Explanation

The general duty clause applies when a hazard was recognized by the employer or the industry, was causing or likely to cause death or serious harm, and a feasible means of abatement existed. Employee injury is not an element, and the clause is used only where no specific standard applies.

Question 18Introduction to OSHA

If an employer refuses to allow an OSHA compliance officer to inspect the workplace, OSHA may:

  1. obtain an inspection warrant from a federal court Correct answer.
  2. treat the refusal as a completed inspection with no findings
  3. impose a citation for obstruction without any further process
  4. enter anyway, because the Act authorizes warrantless inspections

Explanation

In Marshall v. Barlow (1978) the Supreme Court held that an employer may refuse a warrantless inspection, and OSHA must then seek an ex parte warrant from a federal district court. Refusal alone is not an offense.

Question 19Introduction to OSHA

How does NIOSH's role differ from OSHA's in workplace safety?

  1. NIOSH researches hazards and recommends standards without enforcement powers Correct answer.
  2. NIOSH sets the permissible exposure limits that apply to construction work
  3. NIOSH approves state plans on behalf of the Assistant Secretary for OSHA
  4. NIOSH enforces standards by issuing citations and collecting monetary penalties

Explanation

NIOSH is a research agency within the Centers for Disease Control and Prevention. It conducts research, conducts health hazard evaluations, and recommends criteria for standards, but it does not inspect workplaces or cite employers.

Question 20Introduction to OSHA

An employer that disagrees with a citation must contest it:

  1. in writing within 15 working days of receiving the citation Correct answer.
  2. by filing a petition with the U.S. Court of Appeals within 30 days
  3. at any time before the abatement date shown on the citation
  4. orally, during the closing conference with the compliance officer

Explanation

A notice of contest must be filed in writing with the OSHA area director within 15 working days of receiving the citation and proposed penalty. The case is then forwarded to the Occupational Safety and Health Review Commission for adjudication.

Question 21Focus Four Hazards: Falls

Under OSHA construction standards, at what height above a lower level must employees be protected from falls at unprotected sides and edges?

  1. 12 feet
  2. 10 feet
  3. 15 feet
  4. 6 feet Correct answer.

Explanation

29 CFR 1926.501(b)(1) requires fall protection for employees on walking/working surfaces with unprotected sides or edges 6 feet or more above a lower level. Protection may be a guardrail system, safety net system, personal fall arrest system, or a combination of these. The 6-foot trigger applies to most construction trades.

Question 22Focus Four Hazards: Falls

What is the required height range for the top edge of a guardrail system used for fall protection on a construction site?

  1. 50 to 54 inches
  2. 39 to 45 inches Correct answer.
  3. 30 to 36 inches
  4. 45 to 50 inches

Explanation

29 CFR 1926.502(b)(1) requires the top edge of a guardrail to be 42 inches, plus or minus 3 inches, above the walking/working level, which yields a range of 39 to 45 inches. Where the employer can demonstrate this height is not feasible, other height or guardrail configurations may be used if they meet the intent of the standard.

Question 23Focus Four Hazards: Falls

Where must the intermediate (mid) rail of a guardrail system be installed?

  1. Four inches above the surface, where a toeboard would go
  2. Sixteen inches above the walking surface, just above the knee
  3. At the top edge, just below the top rail, to add stiffness
  4. About midway between the top rail and the walking surface Correct answer.

Explanation

29 CFR 1926.502(b)(2) requires a midrail installed at a height midway between the top edge of the guardrail and the walking/working level, roughly 21 inches. Together with the top rail and toeboard, it closes the openings a worker could fall or slide through.

Question 24Focus Four Hazards: Falls

A portable extension ladder is used to reach an upper landing. How far must the side rails extend above the landing surface?

  1. At least 18 inches
  2. At least 12 inches
  3. At least 36 inches Correct answer.
  4. At least 24 inches

Explanation

29 CFR 1926.1053(b)(1) requires portable ladders to extend at least 3 feet above the upper landing surface, or to be secured so that the extension is not needed. The extension provides a handhold when stepping on and off the ladder at the top.

Question 25Focus Four Hazards: Falls

Which practice is acceptable when climbing a portable ladder?

  1. Facing the ladder and keeping three points of contact Correct answer.
  2. Carrying tools in both hands so fewer trips are needed
  3. Standing on the top two rungs to reach a higher level
  4. Moving the ladder while a coworker steadies it by hand

Explanation

Employees must face the ladder and use at least one hand to grasp it while ascending or descending, maintaining three points of contact. Loads that could cause a loss of balance must not be carried by hand. Ladders must also never be moved or shifted while occupied.

Question 26Focus Four Hazards: Falls

What is required of a cover used to protect employees from falling through a floor hole?

  1. Painted a bright color and left easily removable
  2. Made of steel plate and bolted at two corners
  3. Secured against displacement and marked as a cover Correct answer.
  4. At least two inches thick and laid flat on the deck

Explanation

29 CFR 1926.502(i) requires covers to be secured to prevent accidental displacement, color-coded or marked with the word HOLE or COVER, and able to support twice the weight of employees, equipment, and materials imposed on them. Marking is required so employees recognize the opening beneath.

Question 27Focus Four Hazards: Falls

Employees working on a scaffold more than what height above a lower level must be protected by guardrails or a personal fall arrest system?

  1. 6 feet
  2. 10 feet Correct answer.
  3. 4 feet
  4. 15 feet

Explanation

29 CFR 1926.451(g)(1) requires fall protection for employees on a scaffold more than 10 feet above a lower level. This threshold differs from the 6-foot trigger that applies to most other construction walking/working surfaces.

Question 28Focus Four Hazards: Falls

What is the required height range for a guardrail system installed on a supported scaffold?

  1. 36 to 42 inches
  2. 38 to 45 inches Correct answer.
  3. 34 to 39 inches
  4. 30 to 36 inches

Explanation

29 CFR 1926.451(g)(4)(ii) requires scaffold toprails to be installed between 38 and 45 inches above the platform surface. This is slightly different from the 42-inch plus or minus 3 inches rule that applies to general guardrail systems under 1926.502(b).

Question 29Focus Four Hazards: Falls

How should a non-self-supporting portable ladder be positioned against a structure?

  1. One-eighth of the working length out from the base
  2. One-half of the working length out from the base
  3. One-quarter of the working length out from the base Correct answer.
  4. The full working length out from the base

Explanation

The 4-to-1 rule requires the ladder base to be set out one-quarter of the working length of the ladder from the structure, producing an angle of about 75 degrees. Setting the ladder too steeply or too shallowly increases the risk of slipping or tipping.

Question 30Focus Four Hazards: Falls

An anchorage used for a personal fall arrest system must be capable of supporting at least what load per employee attached?

  1. 1,000 pounds
  2. 10,000 pounds
  3. 5,000 pounds Correct answer.
  4. 3,000 pounds

Explanation

29 CFR 1926.502(d)(15) requires anchorages for personal fall arrest systems to support at least 5,000 pounds per employee attached, or to be designed, installed, and used under the supervision of a qualified person as part of a complete system with a safety factor of at least two.

Question 31Focus Four Hazards: Falls

A personal fall arrest system must be rigged so that an employee cannot free fall more than how far, and must limit deceleration distance to how far?

  1. 2 feet; 2 feet
  2. 10 feet; 5 feet
  3. 4 feet; 3 feet
  4. 6 feet; 3.5 feet Correct answer.

Explanation

29 CFR 1926.502(d)(16) requires the system to limit the maximum free fall distance to 6 feet and the deceleration distance to 3.5 feet. The system must also bring the employee to a complete stop and limit maximum arresting force on the body to 1,800 pounds when a body harness is used.

Question 32Focus Four Hazards: Falls

An employee is left suspended in a full body harness after his fall arrest system stops his fall. What must the employer do?

  1. Leave him in the harness until a supervisor arrives to document the event
  2. Rescue him promptly, because suspension can cause serious injury Correct answer.
  3. Allow him to climb back to the work level unassisted in all cases
  4. Give him water and a blanket while waiting for the end of the shift

Explanation

29 CFR 1926.502(d)(20) requires the employer to provide for prompt rescue of employees in the event of a fall, or to assure that employees can rescue themselves. Prolonged suspension in a harness can cause orthostatic intolerance and suspension trauma, which can be fatal within a short time.

Question 33Focus Four Hazards: Falls

When must an employer retrain an employee in fall protection?

  1. Only when a compliance officer finds a violation at the site
  2. Only when the employee requests it in writing from the trainer
  3. Only after an annual refresher course is completed by the crew
  4. When changes on site make prior training obsolete Correct answer.

Explanation

29 CFR 1926.503(c) requires retraining when changes in the workplace or in the types of fall protection equipment make previous training obsolete, or when an employee's conduct shows that he or she has not retained the necessary understanding. Retraining is event-driven rather than tied to a fixed calendar interval.

Question 34Focus Four Hazards: Falls

Workers must lean through an opening in a guardrail to guide a load in a hoist area. What protection does the standard require in this situation?

  1. A toeboard along the shaft edge
  2. A personal fall arrest system Correct answer.
  3. A safety monitoring system
  4. A warning line placed 6 feet back from the edge

Explanation

29 CFR 1926.501(b)(3) states that when a guardrail or portion of it must be removed for hoisting and the employee must lean through the access opening or reach out over the edge, the employee must be protected by a personal fall arrest system. Guardrails alone do not protect a worker whose body passes beyond the rail.

Question 35Focus Four Hazards: Falls

Which statement correctly describes a safety monitoring system?

  1. A competent person watches and warns, with no other duties Correct answer.
  2. It replaces the need for fall protection training of workers
  3. It requires a warning line plus a designated watcher on the roof
  4. It may be used on any roof regardless of slope or roof width

Explanation

Under 29 CFR 1926.502(h), the safety monitor must be a competent person who is on the same walking/working surface, within visual sighting distance and close enough to communicate orally, and who has no other responsibilities that could divert attention from monitoring. The monitor warns employees when they appear unaware of a fall hazard or act unsafely.

Question 36Focus Four Hazards: Falls

A positioning device system must be rigged so that an employee can free fall no more than what distance?

  1. 1 foot
  2. 2 feet Correct answer.
  3. 3.5 feet
  4. 6 feet

Explanation

29 CFR 1926.502(e)(1) requires positioning device systems to be rigged so that an employee cannot free fall more than 2 feet. Positioning systems are meant to hold a worker at the work position and, unlike a personal fall arrest system, are not designed to arrest a long free fall.

Question 37Focus Four Hazards: Falls

A safety net system installed below a work surface must be located at what vertical distance?

  1. Exactly 10 feet below the work surface at all times on every job
  2. At any depth, provided the net has passed a drop test
  3. No more than 5 feet below the work surface on the job
  4. Close to the work surface, never more than 30 feet below Correct answer.

Explanation

29 CFR 1926.502(c)(1) requires safety nets to be installed as close as practicable under the walking/working surface, and in no case more than 30 feet below that level. Net systems must also be drop-tested and inspected weekly, and must extend outward from the work surface by distances that increase with the fall height.

Question 38Focus Four Hazards: Falls

A fall protection plan may be relied on as the means of fall protection only when:

  1. Conventional systems are infeasible or create a greater hazard Correct answer.
  2. The work is performed at heights of 15 feet or less
  3. A competent person is on site at all times during the shift
  4. The building is occupied and its structure cannot be altered

Explanation

29 CFR 1926.502(k) permits a fall protection plan only when the employer can demonstrate that the use of conventional fall protection systems is infeasible or creates a greater hazard. The plan must be prepared by a qualified person, and the written plan must document the site-specific fall hazards and the measures taken to control them.

Question 39Focus Four Hazards: Falls

What defines a controlled access zone on a construction site?

  1. Limited to authorized employees working under a competent person Correct answer.
  2. Access is controlled by a gate that stays locked at all times
  3. A warning line is replaced by a fence around the perimeter
  4. Access is limited to employees who are wearing full body harnesses

Explanation

Under 29 CFR 1926.502(g), a controlled access zone is an area where access is restricted using a control line or other means, and only employees authorized by the employer and working under the direction of a competent person may enter. It is commonly used for leading edge work and overhand bricklaying where other systems are infeasible.

Question 40Focus Four Hazards: Falls

On a roof where mechanical equipment is in use, how far must the warning line be from the roof edge parallel to and perpendicular to the direction of equipment travel?

  1. 3 feet; 6 feet
  2. 6 feet; 6 feet
  3. 6 feet; 10 feet Correct answer.
  4. 10 feet; 10 feet

Explanation

29 CFR 1926.502(f)(2)(iv) requires the warning line to be erected at least 6 feet from the roof edge that is parallel to the direction of mechanical equipment operation, and at least 10 feet from the roof edge that is perpendicular to that direction. The extra distance on the perpendicular sides accounts for equipment that could swing or skid toward the edge.

Question 41Focus Four Hazards: Struck-By

On a construction site where work is being performed overhead, what is the main purpose of the hard hat that OSHA requires?

  1. To keep the head warm in cold weather
  2. To absorb the impact of a falling object Correct answer.
  3. To protect the face from flying particles
  4. To prevent neck strain when lifting heavy materials

Explanation

Hard hats are impact protection for the head: the shell and suspension absorb energy from a falling bolt, brick, or hand tool. They do not protect the neck, keep the head warm, or substitute for eye and face protection.

Question 42Focus Four Hazards: Struck-By

A crane is lifting a bundle of rebar over a work area. Where should the crew stand?

  1. Beside the load, holding it steady by hand
  2. Clear of the load and its travel path Correct answer.
  3. Inside the crane's swing radius to signal the operator
  4. Directly beneath the load to guide it into place

Explanation

Employees must never stand or pass beneath a suspended load, and the fall zone along the load's travel path must be kept clear because a load can shift or rigging can fail without warning. Hand guidance and hard hats do not make the area under a load safe.

Question 43Focus Four Hazards: Struck-By

A flagger is directing traffic on a site that borders a public road. OSHA requires that this worker be provided with and wear:

  1. High-visibility apparel Correct answer.
  2. Hearing protection matched to the noise level
  3. A hard hat with a chin strap
  4. Steel-toed boots with slip-resistant soles

Explanation

OSHA requires flaggers and employees exposed to public vehicular traffic to wear high-visibility warning garments so approaching drivers can see them in time to stop. Hard hats, boots, and hearing protection address other hazards.

Question 44Focus Four Hazards: Struck-By

The primary purpose of a backup alarm on a dump truck is to:

  1. Warn nearby workers that the vehicle is reversing Correct answer.
  2. Warn the operator that the truck is overloaded
  3. Meet federal highway requirements for trucks
  4. Alert mechanics that the transmission needs service

Explanation

A reverse signal alarm that is distinguishable from surrounding noise warns people near the machine that it is about to move backward. It supplements, but never replaces, a spotter's eyes in blind areas.

Question 45Focus Four Hazards: Struck-By

A worker finds that the striking head of a chisel has mushroomed. What should the worker do?

  1. Grind the head down and keep using it
  2. Wrap the head with tape to contain chips
  3. Take it out of service Correct answer.
  4. Wear a face shield and continue using it

Explanation

A mushroomed head can spall and throw metal chips when struck, and tools must be maintained in a safe condition. The tool is removed from service rather than dressed, taped, or used behind a face shield.

Question 46Focus Four Hazards: Struck-By

Which of the following describes a struck-by hazard?

  1. A worker crushed between a truck and a wall
  2. A worker struck by a swinging counterweight Correct answer.
  3. A worker's sleeve caught in a rotating auger
  4. A worker falling from a scaffold platform

Explanation

Struck-by incidents occur when a worker is hit by an object that is falling, flying, swinging, or rolling. A caught sleeve or a worker pinned between equipment and a fixed surface is a caught-in/between event, and a fall from a platform is a fall hazard.

Question 47Focus Four Hazards: Struck-By

An excavator must back up along a haul road where laborers are walking. Which control best reduces the struck-by risk?

  1. Use a trained spotter and keep workers clear Correct answer.
  2. Have the operator sound the horn twice before moving
  3. Tell workers to stay 10 feet from all equipment
  4. Rely on the backup alarm to warn all workers

Explanation

Operators of excavators and other heavy equipment have large blind areas, so alarms and horns are not enough. The employer separates workers from the machine's travel and swing path and uses a trained spotter to direct movement.

Question 48Focus Four Hazards: Struck-By

Before clearing a jammed fastener from a pneumatic nailer, the operator must:

  1. Wear a face shield and leave the air line connected
  2. Point the nose in a safe direction and squeeze the trigger
  3. Ask a coworker to hold the tool steady
  4. Disconnect the air supply Correct answer.

Explanation

Pneumatic tools must be disconnected from the air supply before a jam is cleared or maintenance is performed, because residual pressure can fire a fastener. The tool must also never be pointed at anyone.

Question 49Focus Four Hazards: Struck-By

Steel pipe is stockpiled on a site. Which practice best prevents a struck-by rolling hazard?

  1. Lean the pipe against a site fence
  2. Block or wedge the pipe on level ground Correct answer.
  3. Lay the pipe parallel to the slope
  4. Stack the pipe in a pyramid so weight holds it

Explanation

Cylindrical materials can roll, so they must be stored on level ground and blocked or wedged against movement. Leaning pipe against a fence or storing it where gravity can act on it does not control the hazard.

Question 50Focus Four Hazards: Struck-By

An excavator is working next to a pedestrian walkway. Barricades should be placed to:

  1. Keep workers out of the swing radius Correct answer.
  2. Mark the edge of the excavation
  3. Separate the spoil pile from the trench
  4. Identify underground utility locations

Explanation

OSHA's work-area-control rules require barricades or another effective means to keep employees outside the swing radius of cranes and excavators, where the counterweight or bucket can strike them. Marking the excavation edge or spoil pile does not keep people out of the rotating zone.