SAIA Competent Person — Systems Scaffolds

Under OSHA 1926 Subpart L, who qualifies as a 'competent person' for scaffold work?

• AAny worker with at least 2 years of scaffold experience
• BA person capable of identifying existing and predictable hazards and who has authority to…
• CA licensed structural engineer who has reviewed the scaffold plans
• DA foreman who has attended a 10-hour OSHA construction course

Ring-lock (rosette) and cup-lock systems are both classified as which scaffold type under ANSI A10.8-2019?

• ATube-and-coupler scaffolds
• BSystem (modular) scaffolds
• CFrame and brace scaffolds
• DMast-climbing work platforms

On a ring-lock system scaffold, rosettes are typically spaced at approximately what interval along the vertical standard?

• A0.25 m (approximately 10 inches)
• B0.5 m (approximately 20 inches)
• C1.0 m (approximately 39 inches)
• D1.5 m (approximately 59 inches)

What is the primary function of a transom in a system scaffold?

• ATo provide diagonal bracing in the face of the scaffold
• BTo carry the working platform boards perpendicular to the building face
• CTo resist lateral wind forces by tying into the structure
• DTo extend the working platform beyond the outer standard as a cantilever

OSHA 1926.451(f)(6) specifies minimum electrical clearance distances for uninsulated power lines. What is the minimum clearance required for lines rated 50 kV or below?

• A3 feet (0.9 m)
• B10 feet (3.0 m)
• C15 feet (4.6 m)
• D20 feet (6.0 m)

During erection of a system scaffold, the competent person observes a wet and muddy base condition. Which is the correct response?

• AProceed if the mud depth is less than 6 inches
• BRequire that mudsills, base plates, and screw jacks be installed before continuing
• CDouble the number of ties to compensate for soft ground
• DContact the building owner and wait 48 hours for the soil to dry

The scaffold tagging system uses three colors. What does a YELLOW tag indicate?

• AThe scaffold is fully inspected and safe for use as erected
• BThe scaffold is under construction or has restrictions — use only as directed
• CThe scaffold is unsafe and must not be used
• DThe scaffold has been decommissioned and is awaiting disassembly

At what maximum intervals must vertical ties be provided on a system scaffold, per OSHA 1926.451(c)(1)?

• AEvery 20 feet vertically and every 30 feet horizontally
• BEvery 26 feet vertically and every 30 feet horizontally
• CEvery 30 feet vertically and every 26 feet horizontally
• DEvery 4 scaffold levels vertically and every 3 bays horizontally

What does the 4:1 height-to-base-width ratio rule determine for a freestanding system scaffold?

• AThe maximum allowable platform live load
• BThe height at which the first tie to the structure must be installed
• CThe minimum number of diagonal braces required in each bay
• DThe maximum permitted scaffold height before a licensed engineer is required

A cup-lock scaffold standard uses a lower cup welded to the standard and an upper cup that locks over it. What is the correct assembly sequence when connecting a ledger?

• AInsert the ledger blade into the lower cup, then hammer the upper cup down to lock
• BSlide the upper cup up first, insert the ledger blade into the lower cup, lower the upper…
• CInsert all four ledgers simultaneously and then drop the upper cup in one motion
• DTack-weld the ledger blade to the standard for permanent connection before use

Under OSHA 1926.451(g), when must a personal fall arrest system (PFAS) or guardrail system be provided on a scaffold working platform?

• AOnly when the platform is more than 6 feet above grade on exterior work
• BWhen the working surface is more than 10 feet above a lower level
• COnly on scaffolds taller than 25 feet
• DAt all heights where a worker can fall more than 4 feet

What is a 'mudsill' in system scaffold construction and what is its primary purpose?

• AA rubber isolation pad placed under the base plate to prevent rust
• BA horizontal timber or other load-bearing element that distributes the standard leg load…
• CA grade-level concrete pad poured specifically for scaffold support
• DA steel base plate with leveling bolts that adjusts to uneven surfaces

What maximum leg load does a competent person typically verify before approving a system scaffold leg placement?

• AThe weight of one worker plus their tools
• BThe manufacturer's rated maximum leg load from the technical data sheet
• CThe OSHA standard maximum of 10,000 lb per leg for all system scaffolds
• DAny load up to the rated platform capacity without checking leg load

A system scaffold is being dismantled from the top down. Fall protection for workers on the partially dismantled structure is required because:

• AOnly during initial erection, not dismantling
• BWorkers on partially dismantled scaffolds are at fall risk and OSHA 1926.451(g) applies t…
• COnly when dismantling exceeds 2 stories in height
• DFall protection is optional during dismantling if workers are experienced riggers

What is the primary purpose of diagonal bracing in the face of a system scaffold?

• ATo increase the rated platform live load capacity
• BTo resist racking (shear distortion) of the scaffold frame under lateral loads
• CTo provide additional tie points for anchoring workers' lanyards
• DTo support cantilever hoist arms at the top of the scaffold

When planning a system scaffold adjacent to a sloped roof, what is the competent person's first priority regarding working surface geometry?

• AEnsuring the scaffold platforms slope to match the roof pitch for easier material transfer
• BEnsuring all scaffold standards are plumb and platforms are level using screw jacks and b…
• CPlacing sandbags at the base of uphill legs to prevent sliding
• DReducing the bay width by 50% to account for the slope

A system scaffold platform plank has a crack running parallel to the grain for 18 inches near one end. As the competent person, what action is required?

• AMark the plank with chalk and continue use if no other planks are available
• BRemove the plank from service immediately as it is defective
• CReinforce the crack with a steel strap and return to service
• DRestrict workers to no more than two per bay when the cracked plank is in place

Which of the following is a key erection sequencing rule for Layher Allround ring-lock scaffolds?

• AInstall all ledgers at one level before inserting any standards for the next level
• BErect standards first, then ledgers and transoms at each level, with diagonals installed…
• CInstall diagonal bracing only after the scaffold reaches its full design height
• DConnect ledgers to rosettes using standard pipe couplers before using ring-lock wedges

What is the required minimum width of a fully planked scaffold working platform under OSHA 1926.451(b)(2)?

• A12 inches
• B18 inches
• C24 inches
• D36 inches

What is the maximum allowable extension of a screw jack (adjustable base) beyond the coupling collar of a system scaffold standard, as typically specified by manufacturers?

• A6 inches
• B12 inches
• C18 inches
• D24 inches

A competent person is reviewing a layout plan for a system scaffold with a typical bay size of 2.57 m × 2.57 m (8.4 ft × 8.4 ft). What does 'bay spacing' refer to?

• AThe spacing between platform levels (lift height)
• BThe center-to-center distance between adjacent vertical standards in the horizontal plane
• CThe gap between the scaffold and the building face
• DThe number of rosettes between adjacent ledger connection points

When a system scaffold exceeds the manufacturer's maximum freestanding height, what is the required next step?

• AAdd ballast weights to the base to prevent tipping
• BInstall ties to the structure at the intervals required by OSHA and the manufacturer's de…
• CReduce the bay width by 50%
• DAdd a horizontal brace at mid-height to stiffen the scaffold

What does ANSI A10.8-2019 require regarding erection and dismantling plans for system scaffolds above a specified height?

• ANo written plan is required if the competent person is present at all times
• BA written erection, use, and dismantling plan prepared by a qualified person for scaffold…
• CA plan signed by a licensed structural engineer for any scaffold exceeding 2 lifts
• DPlans are optional but must be kept on site if prepared

How should access stairways on a system scaffold typically be oriented relative to the scaffold face?

• AParallel to the building face with landings every 12 feet maximum
• BPerpendicular to or along the building face within the scaffold structure, with landings…
• CExternal to the scaffold structure, attached only at the top
• DAt a 30-degree angle to the scaffold face to minimize horizontal travel

A competent person conducts a daily pre-shift inspection. Which finding requires immediate work stoppage?

• ALight surface rust on a ledger tube
• BA base plate shifted 2 inches from its original position with no mudsill contact
• CA stair handrail that is 38 inches above the tread nosing
• DA green inspection tag from the previous shift

What is the maximum permissible overhang of a scaffold platform plank beyond its support (transom or ledger) per OSHA 1926.451(b)(3)?

• A6 inches
• B12 inches
• C18 inches
• D24 inches

A hoist arm (gin wheel or electric hoist bracket) is mounted to the top of a system scaffold. What structural consideration must the competent person verify?

• AThat the hoist arm does not extend more than 2 feet beyond the scaffold face
• BThat the hoist load does not exceed the leg load capacity of the standards and that the s…
• CThat the hoist pulley is rated for a minimum 2,000 lb load
• DThat the hoist arm is welded to the top standard for security

What is a cantilevered (fan) platform on a system scaffold and under what condition is engineer involvement typically required?

• AA platform that extends beyond the outer scaffold bay; engineer involvement is required w…
• BA platform on the top working level; engineer involvement is required when height exceeds…
• CA platform over a doorway; engineer involvement is never required for these
• DA suspended platform hanging from the scaffold; always requires a PE stamp

Under OSHA 1926.451(b)(9), the maximum gap between adjacent scaffold planks is:

• ANo gap is permitted
• B1 inch
• C2 inches
• D4 inches

The minimum top rail height of a guardrail on a scaffold working platform per OSHA 1926.451(g)(4) is:

• A36 inches above the platform surface
• B38 inches above the platform surface
• C42 inches above the platform surface (± 3 inches)
• D48 inches above the platform surface

What is the purpose of a toeboard on a scaffold working platform?

• ATo prevent workers from sliding off the platform edge
• BTo prevent tools, materials, and debris from falling off the platform edge to lower levels
• CTo anchor the guardrail posts to the platform decking
• DTo mark the outer edge of the platform for visibility

What does the term 'qualified person' mean in the context of OSHA scaffold regulations, and how does it differ from 'competent person'?

• AThey are the same — both refer to the site supervisor
• BA qualified person has recognized degree, credentials, or professional standing to make s…
• CA qualified person is certified by OSHA; a competent person is certified by the scaffold…
• DA qualified person holds a PE license; a competent person holds an OSHA 30-hour card

A system scaffold is being loaded with masonry block pallets. How should the competent person verify that the scaffold is adequate for this loading?

• AEstimate the weight visually and compare to the number of workers on the platform
• BCalculate the distributed load per platform level and verify it does not exceed the manuf…
• CRely on the general OSHA 25 psf minimum design load for all scaffolds
• DCheck that the platform has at least 4 planks to support palletized material

Where must scaffold access be provided per OSHA 1926.451(e)?

• AOnly at the base and the top working level
• BAt each platform level that is more than 2 feet above or below the point of access
• CAt the ground level only; workers climb the scaffold structure to reach upper levels
• DOnly where specified by the scaffold erection drawings

A Peri Up (modular frame) scaffold is being erected. The erector is about to skip a diagonal brace in a bay because it would interfere with a doorway opening in the scaffold face. What should the competent person do?

• AAllow the omission since the doorway is only one bay wide and the rest of the scaffold is…
• BConsult the manufacturer's erection guide or contact the manufacturer's engineer to appro…
• CAdd an extra tie to the structure in that bay to substitute for the missing brace
• DReduce the platform load in the unbraced bay by 50%

What is the primary function of a 'sole plate' or 'sill plate' when used beneath a mudsill on a system scaffold?

• ATo provide electrical insulation between the scaffold and the ground
• BTo further distribute the concentrated mudsill load over weak or frost-susceptible soil
• CTo lock the mudsill in position and prevent it from sliding under wind load
• DTo mark the scaffold footprint for surveying purposes

In a wind load assessment for a system scaffold, which factor most significantly increases the design wind pressure on the scaffold?

• AThe color of the scaffold components
• BThe presence of solid sheeting or enclosure panels on the scaffold face
• CThe use of steel decking units instead of timber planks
• DThe height of the scaffold above the lowest working level

Before a scaffold is used after an event such as a storm, high winds, or impact from an adjacent crane, OSHA requires:

• ANo additional inspection — the regular daily inspection is sufficient
• BA competent person inspection before workers are permitted to use the scaffold again
• CA licensed engineer's assessment and written sign-off
• DA 24-hour waiting period after the event before use

What information must be recorded on a SAIA-style scaffold inspection tag?

• AOnly the date and the tag color
• BThe scaffold identifier, date of inspection, competent person's name or initials, and any…
• CThe scaffold serial number, erection drawings reference, and engineer of record
• DThe total weight of materials stored on the scaffold and the platform live load rating

What is the maximum permitted gap between a scaffold platform edge and a wall or structure that workers must reach over to perform work?

• A6 inches
• B10 inches
• C14 inches
• D18 inches

Which of the following is NOT a required check during the competent person's daily pre-shift scaffold inspection?

• AVerifying that all base plates and mudsills are in solid contact with the bearing surface
• BChecking that guardrails and mid-rails are intact and properly installed
• CConfirming that scaffold component serial numbers match the erection drawing
• DInspecting all connections (rosettes, cup-lock nodes) for proper seating

What OSHA load category applies to a scaffold used only for painting and light finishing work with a maximum 25 pounds per square foot (psf) load?

• AExtra-light duty
• BLight duty
• CMedium duty
• DHeavy duty

During hazard identification prior to scaffold erection, the competent person notes an overhead electrical line rated 15 kV approximately 8 feet from the planned scaffold location. What is the correct action?

• AProceed — 8 feet exceeds the minimum clearance for lines under 50 kV
• BStop erection and contact the utility company to de-energize or relocate the line before…
• CInstall a rubber mat at the base of the scaffold for insulation
• DRestrict scaffold use to the far side of the structure only

What is the minimum safe working load (SWL) design factor required for scaffold platforms and components per OSHA 1926.451(a)?

• A2:1 (safety factor of 2)
• B3:1 (safety factor of 3)
• C4:1 (safety factor of 4)
• D5:1 (safety factor of 5)

A worker reports that a Layher Allround wedge head no longer locks securely and the wedge can be removed by hand without hammering. What should the competent person do?

• AAllow use but limit loading to 50% of rated capacity in that bay
• BTag the component, remove it from service, and do not allow use until the defective wedge…
• CTighten the wedge by hammering more aggressively and return to service
• DWeld the wedge to the rosette as a field repair

What is 'safe sequencing' in the context of system scaffold dismantling?

• AEnsuring workers are paid for their time in the correct sequence
• BRemoving scaffold components in a top-down, systematic order that maintains structural st…
• CNumbering each component before removal to allow reassembly in the same configuration
• DScheduling dismantling for daylight hours only to improve visibility

A worker approaches the competent person asking why the scaffold is tagged yellow rather than green. The competent person's best response is:

• A'Yellow means the scaffold is inspected — you can use it the same as a green-tagged scaff…
• B'Yellow means the scaffold has restrictions. Here is what you must do before and while us…
• C'Yellow tags are just administrative — the scaffold is safe to use normally'
• D'Ask the foreman — the tag system is not my responsibility'