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NCCER Scaffolder study materials
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NCCER Scaffolder practice questions

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Question 1Scaffold Safety Fundamentals and Hazard Awareness

At what height above a lower level must employees working on a supported scaffold be protected from falling?

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

Explanation

The scaffold standard requires fall protection, either a guardrail system or a personal fall arrest system, for employees working on a scaffold more than 10 feet above a lower level. Below that height, fall protection is not mandated by the scaffold rule, although guardrails are commonly installed anyway.

Question 2Scaffold Safety Fundamentals and Hazard Awareness

What is the required height range for a scaffold toprail, measured from the platform surface to the top edge of the rail?

  1. 50 to 60 inches
  2. 30 to 36 inches
  3. 38 to 45 inches Correct answer.
  4. 44 to 50 inches

Explanation

A toprail must be installed so its top edge is between 38 and 45 inches above the platform surface. This range keeps the rail high enough to arrest a fall and low enough to be effective.

Question 3Scaffold Safety Fundamentals and Hazard Awareness

What is the minimum required horizontal clearance between a scaffold and insulated power lines carrying less than 50 kV?

  1. 25 feet
  2. 10 feet Correct answer.
  3. 3 feet
  4. 6 feet

Explanation

The minimum clearance for insulated lines under 50 kV is 10 feet, with greater distances required as voltage rises. The clearance protects workers and conductive scaffold components from contact or arc flash.

Question 4Scaffold Safety Fundamentals and Hazard Awareness

A competent person on a scaffold job is best described as someone who:

  1. can identify hazards and is authorized to correct them Correct answer.
  2. holds a current state-issued scaffolding contractor license
  3. has completed an OSHA 30-hour construction course
  4. has at least five years of documented field experience

Explanation

A competent person is defined by two elements: the ability to recognize existing and predictable hazards, and the authority to take prompt corrective action. Training, experience, and licensing may support that ability but do not replace the delegated authority.

Question 5Scaffold Safety Fundamentals and Hazard Awareness

Which method is acceptable for reaching a scaffold work platform?

  1. Climbing the end frames or crossbraces
  2. Using a ladder or stair tower Correct answer.
  3. Walking up a loose plank ramp
  4. Being lifted by a co-worker from below

Explanation

Access must be provided by a designed means such as a ladder, stairway, ramp, or personnel hoist. Crossbraces and end frames are structural members, not ladders, and climbing them is prohibited.

Question 6Scaffold Safety Fundamentals and Hazard Awareness

What is the minimum height, measured from the walking surface to the top edge, for a toeboard?

  1. 2 inches
  2. 6 inches
  3. 3 1/2 inches Correct answer.
  4. 8 inches

Explanation

Toeboards must be at least 3 1/2 inches high from the top edge to the level of the walking surface, with no more than 1/4 inch clearance above the surface. Their purpose is to keep tools and materials from being kicked off the platform.

Question 7Scaffold Safety Fundamentals and Hazard Awareness

A scaffold in use must be inspected by a competent person:

  1. after every 30 days of continuous use
  2. only at the time of the initial erection
  3. once each week for as long as it is in use
  4. before each shift and after events affecting it Correct answer.

Explanation

Scaffolds must be inspected before each work shift and after any occurrence that could affect structural integrity, such as high winds, impacts, or alterations. A weekly or one-time inspection would miss damage that develops between shifts.

Question 8Scaffold Safety Fundamentals and Hazard Awareness

Which control protects employees working below a scaffold from falling objects?

  1. Toeboards, screens, or debris nets Correct answer.
  2. Requiring hard hats for workers below
  3. Posting warning signs at the entrance
  4. Stopping hoisting when people are below

Explanation

Where falling object hazards exist, the platform must be equipped with toeboards, and where tools or materials could fall farther, screens, debris nets, or canopies are needed. Barricades keep employees out of the hazard area as well.

Question 9Scaffold Safety Fundamentals and Hazard Awareness

Scaffold legs and frames must be supported by:

  1. stacked concrete blocks or loose masonry
  2. loose cribbing made from scrap lumber
  3. base plates on mud sills or firm footing Correct answer.
  4. bare ground with no base plates

Explanation

Legs must rest on base plates that bear on mud sills or another firm footing capable of supporting the loaded scaffold without settling. Loose masonry and scrap cribbing can crush or shift and are prohibited.

Question 10Scaffold Safety Fundamentals and Hazard Awareness

What is the minimum width of a scaffold platform or walkway, unless the employer can demonstrate that a narrower platform is adequate?

  1. 24 inches
  2. 12 inches
  3. 15 inches
  4. 18 inches Correct answer.

Explanation

Each scaffold platform and walkway must be at least 18 inches wide. The 18-inch minimum gives workers room to stand and move while carrying tools and materials.

Question 11Scaffold Safety Fundamentals and Hazard Awareness

Wood scaffold planks should be:

  1. painted on the walking surface for visibility
  2. coated with opaque paint for weather protection
  3. covered with sealer to hide knots
  4. left unpainted except for edge identification marks Correct answer.

Explanation

Opaque finishes can hide cracks, knots, and other defects that must be visible during inspection, so only the edges may be marked or covered for identification. Clear or transparent coatings that allow defect inspection are acceptable.

Question 12Scaffold Safety Fundamentals and Hazard Awareness

Which rule applies to employees on a mobile scaffold?

  1. They must be tied off to the frame
  2. They may ride it if it is moved slowly
  3. They must get off before it is moved Correct answer.
  4. They may ride it only on level floors

Explanation

Employees must never ride a moving mobile scaffold; they must descend before the unit is moved. Casters must also be locked and the scaffold leveled before work begins.

Question 13Scaffold Safety Fundamentals and Hazard Awareness

Counterweights used on suspension scaffold outrigger beams must be:

  1. placed on any flat surface near the beam
  2. attached with rope so they can be adjusted
  3. secured to the beam and non-flowable Correct answer.
  4. made of sand or water in approved containers

Explanation

Counterweights must be made of a non-flowable material and must be secured to the outrigger beam so they cannot be dislodged or removed. Sand, water, and loose material can leak or shift and are not acceptable.

Question 14Scaffold Safety Fundamentals and Hazard Awareness

When welding or cutting is performed near fiber suspension ropes, the ropes must be:

  1. inspected only after the work is finished
  2. protected from heat or replaced with wire rope Correct answer.
  3. left in place because fiber rope will not burn
  4. wetted down before each shift

Explanation

Fiber rope is easily damaged by heat, sparks, and slag, so it must be shielded or replaced with wire rope when hot work is nearby. Damaged suspension rope can fail without warning.

Question 15Scaffold Safety Fundamentals and Hazard Awareness

The bottom rung of a portable ladder used for scaffold access must be no more than:

  1. 18 inches above the supporting level
  2. 24 inches above the supporting level Correct answer.
  3. 12 inches above the supporting level
  4. 36 inches above the supporting level

Explanation

The bottom rung of an access ladder may not be more than 24 inches above the scaffold supporting level, and ladders must also extend above the landing as required. A lower first step keeps the climb controlled.

Question 16Scaffold Safety Fundamentals and Hazard Awareness

Portable electric tools used on a scaffold must be supplied through:

  1. a GFCI-protected circuit Correct answer.
  2. a temporary splice in the supply cord
  3. any convenient outlet on the floor
  4. an extension cord without a ground prong

Explanation

Temporary power on construction sites, including tools used on scaffolds, must be protected by ground-fault circuit interrupters. The GFCI de-energizes the circuit quickly if current leaks to ground through a worker or wet scaffold.

Question 17Scaffold Safety Fundamentals and Hazard Awareness

Supported scaffold frames and poles must be installed:

  1. leaning slightly toward the structure
  2. set on any convenient firm surface
  3. braced only at the topmost level
  4. plumb, level, and braced against sway Correct answer.

Explanation

Poles, legs, posts, and frames must be plumb, level, and braced to prevent swaying and displacement. Bracing only at the top leaves the lower portion free to shift or rack.

Question 18Scaffold Safety Fundamentals and Hazard Awareness

A scaffold component that is bent, cracked, or heavily rusted must be:

  1. used only on the lowest level
  2. straightened and put back in use
  3. tagged and removed from service Correct answer.
  4. painted to prevent further rust

Explanation

Damaged or weakened components must be repaired or replaced before use and kept out of service until then. Straightening or painting a damaged member does not restore its strength.

Question 19Scaffold Safety Fundamentals and Hazard Awareness

When a worker on a suspension scaffold uses a personal fall arrest system, the employer must make sure that:

  1. the system is anchored to a guardrail
  2. the lanyard is longer than six feet
  3. the worker can be rescued promptly Correct answer.
  4. the worker is alone on the platform

Explanation

A plan must exist to retrieve a worker promptly after an arrested fall, because suspension in a harness can cause serious injury within minutes. Rescue equipment and trained rescuers must be available.

Question 20Scaffold Safety Fundamentals and Hazard Awareness

Work on a scaffold must be suspended whenever:

  1. a light drizzle begins to fall
  2. high winds or storms create a hazard Correct answer.
  3. more than three workers are on the platform
  4. the temperature falls below freezing

Explanation

Work must stop when scaffolds are covered with ice or snow, during storms or high winds, or whenever conditions make the work hazardous. Wind loading and wet or icy decks greatly increase collapse and slip risk.

Question 21Scaffold Safety Fundamentals and Hazard Awareness

Every scaffold and scaffold component must support, without failure, its own weight plus at least:

  1. 1.5 times the maximum intended load
  2. 4 times the maximum intended load Correct answer.
  3. 8 times the maximum intended load
  4. 2 times the maximum intended load

Explanation

The design safety factor for scaffolds and components is four, meaning the structure must carry its own weight plus at least four times the maximum intended load. This margin covers impact, uneven loading, and minor defects.

Question 22Scaffold Safety Fundamentals and Hazard Awareness

A supported scaffold is 24 feet tall and its base dimension is 4 feet. What must be done?

  1. A wider deck of at least 24 inches must be installed
  2. The scaffold must be restrained by guying, tying, or bracing Correct answer.
  3. The top working level must be removed
  4. Nothing extra, because height does not affect stability

Explanation

The height-to-base ratio is 24 divided by 4, or 6:1, which exceeds the 4:1 limit for an unrestrained supported scaffold. The scaffold must therefore be restrained from tipping by guying, tying to the structure, or bracing.

Question 23Scaffold Safety Fundamentals and Hazard Awareness

During the erection and dismantling of a supported scaffold, fall protection is required:

  1. only when the scaffold exceeds 10 feet
  2. never, because the scaffold is incomplete
  3. only above 20 feet
  4. for exposed employees unless shown to be infeasible Correct answer.

Explanation

Employees erecting or dismantling supported scaffolds must be protected from falls, for example by a personal fall arrest system or a supported platform with guardrails, unless the employer can demonstrate that installation of the protection is infeasible.

Question 24Scaffold Safety Fundamentals and Hazard Awareness

When a scaffold platform is loaded, its deflection must not exceed:

  1. 1/60 of the span Correct answer.
  2. 1 inch regardless of the span
  3. 1/120 of the span
  4. 1/30 of the span

Explanation

Platforms may not deflect more than 1/60 of the span under load. Excessive deflection makes the deck springy, trips workers, and can overload or displace planks.

Question 25Scaffold Safety Fundamentals and Hazard Awareness

Each suspension rope on an adjustable suspension scaffold must be capable of supporting, without failure, at least:

  1. 3 times the maximum intended load
  2. 4 times the maximum intended load
  3. 6 times the maximum intended load Correct answer.
  4. 8 times the maximum intended load

Explanation

Suspension ropes and their connecting hardware carry the entire platform and must have a safety factor of six against the maximum intended load. This higher factor accounts for wear, dynamic loading, and the consequences of a rope failure.

Question 26Scaffold Safety Fundamentals and Hazard Awareness

On a supported scaffold, where must the top edge of the top rail be?

  1. 24 to 30 inches above the platform
  2. 46 to 52 inches above the platform
  3. 54 to 60 inches above the platform
  4. 38 to 45 inches above the platform Correct answer.

Explanation

Scaffold top rails must be installed with the top edge 38 to 45 inches above the platform. This range provides a usable height for fall protection without making the rail difficult to work over.

Question 27Scaffold Safety Fundamentals and Hazard Awareness

At what height above a lower level must employees on a supported scaffold be protected from falling?

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

Explanation

Employees on a supported scaffold must be protected from falling when the platform is more than 10 feet above a lower level. Guardrails, personal fall arrest, or another approved system may be used.

Question 28Scaffold Safety Fundamentals and Hazard Awareness

Unless a greater distance is required by the utility, how far must a scaffold and its conductive materials stay from exposed energized power lines?

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

Explanation

Scaffolds and conductive materials on them must stay at least 10 feet from exposed energized power lines unless the utility requires more distance. This clearance helps prevent contact and electrical arc hazards.

Question 29Scaffold Safety Fundamentals and Hazard Awareness

Employees find a scaffold platform covered with ice. What must happen before work begins on that platform?

  1. Work may begin if workers move slowly
  2. The ice must be removed and the surface made safe Correct answer.
  3. Work may begin if guardrails are installed
  4. Sand may be spread over the ice

Explanation

Employees must not work on a scaffold platform that is covered with ice or snow or is otherwise slippery. The ice must be removed and the platform made safe before use.

Question 30Scaffold Safety Fundamentals and Hazard Awareness

Where is a midrail installed in a scaffold guardrail system?

  1. Six inches below the top rail
  2. Directly on top of the toeboard
  3. Midway between the top rail and the platform Correct answer.
  4. Twelve inches above the platform surface

Explanation

When midrails are used, they must be installed midway between the top rail and the platform. This placement closes the opening so a worker or object cannot pass under the top rail.

Question 31Scaffold Safety Fundamentals and Hazard Awareness

What is the maximum allowed gap between adjacent platform units on a scaffold?

  1. Three inches
  2. Two inches
  3. One-half inch
  4. One inch Correct answer.

Explanation

Adjacent platform units and platform edges must be placed so the gap does not exceed 1 inch, unless a wider space is specifically justified. Small gaps help prevent tools and feet from slipping through.

Question 32Scaffold Safety Fundamentals and Hazard Awareness

When scaffold planks are overlapped, what is the minimum overlap?

  1. 6 inches
  2. 3 inches
  3. 12 inches Correct answer.
  4. 18 inches

Explanation

Overlapping scaffold planks must overlap by at least 12 inches and must be secured against movement. The overlap keeps the platform continuous and stable.

Question 33Scaffold Safety Fundamentals and Hazard Awareness

A scaffold platform is 3 feet above the only point of access. What must the employer provide?

  1. Nothing until the platform is 5 feet high
  2. A ladder, stairway, or other safe access Correct answer.
  3. A sign directing workers to climb the frame
  4. A warning line around the access point

Explanation

Safe access is required whenever a scaffold platform is more than 2 feet above or below a point of access. A ladder, stairway, or other safe means must be provided.

Question 34Scaffold Safety Fundamentals and Hazard Awareness

A scaffold guardrail system must withstand what minimum force, without failure, in an outward or downward direction?

  1. 200 pounds Correct answer.
  2. 50 pounds
  3. 100 pounds
  4. 400 pounds

Explanation

Guardrail systems on scaffolds must be able to withstand at least 200 pounds applied near the top edge in an outward or downward direction. This strength helps the rail stop a worker's fall.

Question 35Scaffold Safety Fundamentals and Hazard Awareness

An employee on a scaffold demonstrates a lack of understanding of a scaffold hazard. What must the employer do?

  1. Retrain the employee on the hazard Correct answer.
  2. Wait until the next annual training
  3. Move the employee to another scaffold
  4. Document the issue and take no action

Explanation

The employer must retrain an employee when there is reason to believe the employee lacks the understanding needed to work safely on a scaffold. Moving the worker or waiting for annual training does not correct the hazard.

Question 36Scaffold Safety Fundamentals and Hazard Awareness

A scaffold leg is 2 inches above firm ground. What is the correct way to support it?

  1. Wedge a piece of scrap lumber under the leg
  2. Use an adjustable base designed for the scaffold Correct answer.
  3. Stack two concrete blocks under the leg
  4. Place a loose brick under the leg

Explanation

Scaffold legs must bear on base plates and firm foundations, and adjustable bases are designed for this purpose. Barrels, blocks, bricks, and scrap wood are unstable and prohibited as supports.

Question 37Scaffold Safety Fundamentals and Hazard Awareness

Unless guardrails or personal fall arrest protect the front edge, a scaffold platform must be no more than what distance from the face of the work?

  1. 18 inches
  2. 10 inches
  3. 6 inches
  4. 14 inches Correct answer.

Explanation

A scaffold platform must be no more than 14 inches from the face of the work unless guardrails or personal fall arrest protect the front edge. This limit reduces the chance of a worker or material falling through the gap.

Question 38Scaffold Safety Fundamentals and Hazard Awareness

Who may erect, move, dismantle, or alter a scaffold?

  1. Any employee who has worked on scaffolds
  2. Only a licensed professional engineer
  3. Trained employees supervised by a competent person Correct answer.
  4. Any employee wearing fall protection

Explanation

Scaffolds must be erected, moved, dismantled, or altered only by trained and experienced employees under the supervision of a competent person. Scaffold work is not assigned to untrained workers.

Question 39Scaffold Safety Fundamentals and Hazard Awareness

A worker on a scaffold uses a personal fall arrest system. To what may the lanyard be attached?

  1. The toeboard
  2. The midrail of the guardrail system
  3. The top rail of the guardrail system
  4. A scaffold structural member Correct answer.

Explanation

Personal fall arrest lanyards must attach to a scaffold structural member or to a lifeline, not to guardrail components. Guardrails and toeboards are not designed to serve as anchorages.

Question 40Scaffold Safety Fundamentals and Hazard Awareness

Scaffold components from different manufacturers may be combined only when the components do what?

  1. Have been approved in writing by the site foreman
  2. Are used only on scaffolds less than 10 feet high
  3. Fit together without force and remain structurally sound Correct answer.
  4. Have the same finish, color, and manufacturer's markings

Explanation

Components from different manufacturers may be combined only if they fit together without force and the scaffold remains structurally sound. Forcing or modifying mismatched parts can cause the scaffold to fail.

Question 41Scaffold Components, Materials, and Fittings

In a tube-and-coupler scaffold, which component is the vertical member that carries the load down to the base plate?

  1. Transom
  2. Cross brace
  3. Ledger
  4. Standard Correct answer.

Explanation

The upright tube in a tube-and-coupler scaffold is called the standard (also known as a post or leg). Standards carry the platform load vertically down to the base plates and mud sills.

Question 42Scaffold Components, Materials, and Fittings

Which statement best describes a ledger on a tube-and-coupler scaffold?

  1. A horizontal member that rests on the ledgers and supports the platform planks
  2. A horizontal member that runs parallel to the face of the scaffold and connects the standards Correct answer.
  3. A diagonal member fastened between standards to keep the scaffold square
  4. A short member placed under each standard to spread the load into the ground

Explanation

Ledgers are the long horizontal tubes that tie the standards together along the length of the scaffold. They carry the transoms and stiffen the structure in the horizontal direction.

Question 43Scaffold Components, Materials, and Fittings

What is the primary purpose of a base plate under a scaffold standard?

  1. To spread the load from the standard over the mud sill or footing Correct answer.
  2. To tie the scaffold to the structure being worked on
  3. To adjust the height of the scaffold during erection
  4. To keep the standards from rotating inside the couplers

Explanation

Base plates bear on a mud sill or other firm footing and distribute the concentrated leg load over a larger area. This prevents the standard from punching into the ground or the supporting surface.

Question 44Scaffold Components, Materials, and Fittings

Why are cross braces installed on a frame scaffold?

  1. To give workers a ladder for climbing between levels
  2. To keep the frames square and provide lateral stability Correct answer.
  3. To carry the platform planks between the transoms
  4. To transfer the platform load directly to the mud sills

Explanation

Cross braces lock the frames into square and resist side-to-side movement, which is essential to the stability of the tower. They are structural bracing and are not intended as a load path for the platform.

Question 45Scaffold Components, Materials, and Fittings

Toe boards installed along the edge of a scaffold platform are intended mainly to:

  1. Keep tools, materials, and debris from being kicked off the platform Correct answer.
  2. Support the midrail from below
  3. Increase the load rating of the platform
  4. Serve as an anchor point for personal fall arrest systems

Explanation

Toe boards form a barrier at the deck edge so objects cannot easily slide or be kicked off and strike workers below. They supplement the guardrail system but do not replace any part of it.

Question 46Scaffold Components, Materials, and Fittings

Which marking must a wood plank carry before it can be used as a scaffold platform?

  1. A paint stripe applied by the supplier
  2. A grade stamp from a recognized grading agency showing scaffold grade Correct answer.
  3. A stamp showing the plank has been treated with preservative
  4. A mill stamp indicating the lumber was kiln dried

Explanation

Scaffold planking must be graded by an approved grading agency and marked with a stamp that identifies it as scaffold grade. The grade stamp is the evidence that the plank has the strength and defect limits required for platform use.

Question 47Scaffold Components, Materials, and Fittings

What is the minimum required width of a scaffold platform used by employees?

  1. 24 inches
  2. 12 inches
  3. 30 inches
  4. 18 inches Correct answer.

Explanation

Platforms and walkways must be at least 18 inches wide unless the employer can show that a narrower platform is a greater hazard or the work requires it. A narrower deck leaves too little footing for a worker carrying tools or materials.

Question 48Scaffold Components, Materials, and Fittings

How high above the platform must the top edge of a guardrail system be installed?

  1. 30 to 36 inches
  2. 48 to 54 inches
  3. 38 to 45 inches Correct answer.
  4. 42 to 50 inches

Explanation

The top edge of a toprail must be 38 to 45 inches above the walking/working surface. This range is high enough to stop a falling worker but low enough to be reached and gripped comfortably.

Question 49Scaffold Components, Materials, and Fittings

What is the purpose of a mud sill under a scaffold?

  1. To spread the base plate load over a larger area of ground Correct answer.
  2. To protect the base plate from corrosion
  3. To anchor the standards to the ground
  4. To raise the working height of the scaffold

Explanation

A mud sill is a sturdy timber or pad placed under the base plate so the leg load is distributed over a larger bearing area. It reduces settlement and keeps the scaffold from sinking into soft or disturbed soil.

Question 50Scaffold Components, Materials, and Fittings

Which coupler is used to fasten a ledger to a standard at a 90-degree angle?

  1. Right-angle coupler Correct answer.
  2. Swivel coupler
  3. Putlog coupler
  4. Sleeve coupler

Explanation

A right-angle (double) coupler is made to join two tubes that cross at 90 degrees and is designed to carry load without slipping. It is the standard fitting for connecting ledgers and transoms to standards.