CTVET Ghana Certificate II — Blocklaying and Concreting (Ghana)

Which Ghanaian legislation establishes the legal framework for occupational safety, health, and welfare standards on construction sites?

• AThe Environmental Protection Agency Act, 1994 (Act 490)
• BThe Factories, Offices and Shops Act, 1970 (Act 328)
• CThe Workmen's Compensation Act, 1987 (PNDCL 187)
• DThe Ghana National Fire Service Act, 1997 (Act 537)

According to safe construction practices in Ghana, when must an erected scaffold on a masonry site be inspected?

• AOnly when the project reaches the practical completion stage
• BBefore first use, after any alterations, and after exposure to adverse weather conditions
• COnce every three months by the main contractor's site surveyor
• DOnly after an accident or structural failure has occurred on-site

What is the primary hazard to a mason's skin when handling wet cement mortar without gloves?

• ASevere chemical burns and allergic contact dermatitis due to the high alkalinity of cement
• BSkin discoloration due to the high iron oxide content in local clay bricks
• CMild bacterial infections caused by microorganisms in sand
• DDehydration from the evaporation of curing water on the skin

Which class of fire involves combustible materials such as timber scaffolding and wood formwork on a masonry site?

• AClass A fire
• BClass B fire
• CClass C fire
• DClass D fire

What safety measure is mandatory when excavating a foundation trench deeper than 1.5 meters on a construction site in Ghana?

• AProviding a temporary plastic dust sheet over the trench floor
• BInstalling timber shoring or battering the trench sides to prevent collapse
• CFlooding the trench with water to compact the subgrade before masonry work
• DDecreasing the width of the trench to increase lateral soil pressure

What is the meaning of a blue, circular safety sign displayed on a Ghanaian building site?

• ADanger or high-risk warning
• BMandatory action (e.g., must wear safety helmet)
• CProhibition (e.g., no entry)
• DSafe conditions and emergency exit routes

At what height must a mason wear a full-body fall arrest harness connected to a secure anchor point on a construction site?

• AOnly when working above 10 meters
• BWhen working at a height of 2 meters or above where there is a risk of falling
• COnly when working on roofs with a slope greater than 45 degrees
• DHarnesses are never required if the scaffold has guard rails

What is the long-term respiratory risk associated with continuous inhalation of fine dry cement dust and silica sand dust on construction sites?

• ACardiovascular blockages due to calcium deposits in veins
• BOccupational asthma, bronchitis, and silicosis (scarring of lung tissue)
• CTemporary carbon monoxide poisoning
• DGastrointestinal tract inflammation

If wet cement or mortar splashes into a worker's eyes, what is the immediate first aid response required on-site?

• ARubbing the eyes vigorously with dry cement paper bags to absorb moisture
• BFlushing the eyes immediately with clean water for at least 15 minutes and seeking medica…
• CApplying vinegar or lemon juice to neutralize the alkaline cement
• DCovering the eyes with a dry bandage and continuing block laying

How should petrol and diesel fuel for site equipment (like concrete mixers and generators) be stored to comply with site safety standards?

• AIn open plastic buckets placed near the exhaust of the running mixer
• BIn approved metal safety containers stored in a well-ventilated, secure area away from ig…
• CIn glass bottles placed on top of cement stacks to keep them dry
• DInside the main lunchroom area to prevent theft by site workers

What is the correct angle or ratio for placing a portable ladder against a scaffold platform or wall?

• A1 horizontal to 1 vertical (45 degrees)
• B1 horizontal to 4 vertical (75 degrees)
• C1 horizontal to 10 vertical (84-degree incline)
• DAny angle is acceptable as long as the ladder is tied off at the top

Which document must be available on-site to provide safety and handling information for chemicals like formwork release agents and curing compounds?

• AThe contractor's bank statement
• BSafety Data Sheet (SDS) / Material Safety Data Sheet (MSDS)
• CThe local municipal building permit
• DThe client's land title deed

What is the correct manual lifting posture for a mason moving heavy concrete blocks on a site?

• ABending at the waist with straight legs and pulling the block upwards quickly
• BBending the knees, keeping the back straight, and lifting using the leg muscles
• CTwisting the spine while lifting to swing the block onto a wheelbarrow
• DLifting the block using only one arm to keep the other arm free for support

Which safety device should be connected to temporary electrical power boards on construction sites to protect workers from electric shock?

• AA mechanical pressure valve
• BResidual Current Device (RCD) / Earth Leakage Circuit Breaker (ELCB)
• CA bypass copper wire bridge
• DA voltage-free transformer regulator

What is the purpose of installing toeboards on scaffold working platforms where masons are laying blocks?

• ATo provide a footrest for workers during rest breaks
• BTo prevent tools, mortar, and blocks from falling off the platform edge onto people below
• CTo increase the structural load capacity of the scaffold standards
• DTo align the scaffold boards horizontally during installation

Which hand tool is specifically designed for cutting concrete blocks and bricks cleanly when struck with a hammer?

• AA plastering trowel
• BA bolster chisel
• CA spirit level
• DA jointing iron

How can a mason verify that the vertical face of a block wall is perfectly upright during construction?

• ABy placing a straight edge horizontally across the wall face
• BBy using the vertical vial of a spirit level or a plumb bob
• CBy measuring the diagonal lines of the building outline
• DBy looking at the shadow cast by the wall at noon

What is the primary function of a plumb bob in masonry works?

• ATo mix small quantities of plastering mortar
• BTo transfer a vertical point from a height to the ground or check verticality
• CTo measure the moisture content of concrete blocks
• DTo strike the mortar joint to create a recessed profile

Which tools are used to secure and tension a nylon line along a course of blocks during bricklaying?

• ABolster chisels and hammers
• BLine pins or corner blocks
• CSteel floats and hawks
• DPlumb bobs and straight edges

What is the best maintenance practice for a brick trowel at the end of a block laying shift?

• ACoating the blade with wet sand to keep it moist
• BScraping off mortar, washing the blade with clean water, drying it, and applying light oil
• CLeaving the trowel inside a bucket of wet mortar to prevent drying
• DSharpening the trowel edge to a razor-sharp finish using an angle grinder

What is the primary purpose of a hawk (or handboard) in plastering and rendering operations?

• ATo compact subgrade soil in tight trench corners
• BTo hold a small quantity of mortar or plaster ready for application with a trowel
• CTo cut concrete blocks at precise angles
• DTo check the horizontal level of a newly laid concrete floor

Why is a mashing hammer (or club hammer) preferred over a standard claw hammer for masonry work?

• AIt has a curved claw for pulling reinforcement steel wires
• BIt has a heavy, double-faced head designed to strike chisels and split blocks
• CIt is lighter and easier to swing continuously when driving wood nails
• DIt has a soft rubber head that prevents damage to clay bricks

What is the recommended sequence for adding ingredients into a mechanical drum mixer to mix concrete?

• ADry cement first, then gravel, then sand, and finally all of the water
• BSome water first, then coarse aggregate, fine aggregate, cement, and the remaining water
• CSand and cement mixed dry in the drum for 10 minutes before adding any aggregates
• DDump all materials in simultaneously while the mixer drum is stationary

Which tool is best suited for adjusting the horizontal level of a building profile board during setting out?

• AA mashing hammer and a tingle plate
• BA straight edge and a spirit level (or a water level tube)
• CA bolster chisel and line pins
• DA steel float and a hawk

What is the function of a tingle plate (or line tingle) used in masonry operations?

• ATo cut concrete blocks into thin slices
• BTo support a long building line, preventing it from sagging in the middle due to its own…
• CTo anchor the scaffolding to the block wall
• DTo measure the width of mortar joints

What are the standard dimensions of a load-bearing concrete hollow block commonly used for external walls in Ghana?

• A100mm x 100mm x 300mm
• B150mm x 225mm x 450mm
• C200mm x 200mm x 200mm
• D75mm x 115mm x 230mm

What is the maximum permissible silt content by volume in sand used for making structural concrete or mortar?

• A1%
• B8%
• C25%
• D50%

Which grade of Portland cement is recommended for structural concrete works like beams and slabs in Ghana?

• AGrade 12.5 (Masonry Cement)
• BGrade 42.5R or 42.5N
• CGrade 22.5
• DAny grade is suitable as long as extra water is added

What is the phenomenon called when damp sand increases in volume compared to dry sand?

• AThermal expansion of silica
• BBulking of sand
• CSilt coagulation
• DHydration of fine aggregates

What is the standard initial setting time for Ordinary Portland Cement (OPC) under normal conditions?

• ANot less than 5 minutes
• BNot less than 30 minutes
• CExactly 24 hours
• DBetween 10 and 12 hours

What is the standard maximum size of coarse aggregate (gravel) typically used for structural concrete in thin, reinforced sections?

• A5mm
• B20mm
• C75mm
• D150mm

Which mortar mix ratio (cement:sand) by volume is standard for laying load-bearing external sand-cement block walls?

• A1:1
• B1:4
• C1:10
• D1:20

What is the recommended cement:sand mix ratio by volume for external rendering (plastering) of block walls in Ghana?

• A1:2
• B1:5 or 1:6
• C1:12
• DPure cement paste without sand

What feature distinguishes high-yield steel reinforcement bars from mild steel bars in construction?

• AThey have a smooth, polished surface
• BThey have a ribbed surface to improve mechanical bonding with concrete
• CThey are painted blue to prevent rusting on-site
• DThey can be bent easily by hand without tools

How should reinforcing steel bars affected by rust be treated before being placed in concrete formwork?

• AThey must be coated with heavy lubricating oil to prevent further rusting
• BLoose, flaking rust must be brushed off, but light rust is acceptable as it improves bond…
• CThey must be painted with red oxide paint before concrete placement
• DThey must be heated until red-hot to burn off the rust

What is the chemical reaction called that takes place when water is added to cement, causing it to set and harden?

• AEvaporation
• BHydration
• CCarbonation
• DOxidation

What is the effect of using too much water in a concrete mix (high water-cement ratio)?

• AIt increases the ultimate compressive strength of the concrete
• BIt reduces strength, increases porosity, and leads to high shrinkage cracks
• CIt prevents the concrete from setting at all
• DIt makes the concrete less workable during placement

Which of the following field tests is used to determine the presence of organic silt impurities in sand on-site?

• AThe concrete slump test
• BThe sand silt jar test (shaking sand in a salt-water solution)
• CThe rebound hammer test
• DThe Vicat needle test

What is the volumetric composition represented by a standard 1:2:4 concrete mix ratio?

• A1 part sand, 2 parts gravel, 4 parts cement
• B1 part cement, 2 parts sand (fine aggregate), 4 parts gravel (coarse aggregate)
• C1 part cement, 2 parts lime, 4 parts water
• D1 part water, 2 parts cement, 4 parts sand

Why is rapid-hardening Portland cement sometimes used instead of Ordinary Portland Cement?

• AIt is cheaper to manufacture and buy in Ghana
• BIt gains strength faster, allowing earlier removal of concrete formwork
• CIt requires no water curing whatsoever
• DIt has a lower chemical heat of hydration

What quality of water must be used for mixing concrete and mortar to ensure proper chemical setting?

• ASeawater to speed up concrete curing
• BPotable (drinking) water free from acids, alkalis, organic matter, and salts
• CMuddy water from foundation excavations to conserve water
• DUntreated industrial wastewater containing organic chemicals

What is concrete segregation?

• AThe setting of concrete in different colors
• BThe separation of coarse aggregates from the cement mortar mix during handling
• CThe chemical reaction between cement and steel reinforcement
• DThe process of cutting joints in green concrete

What is the primary benefit of adding a small amount of hydrated lime to a cement-sand mortar mix?

• AIt makes the mortar set instantly
• BIt improves the mortar's workability, water retention, and flexibility
• CIt doubles the ultimate compressive strength of the brickwork
• DIt prevents the mortar from absorbing water during mixing

What is efflorescence on a block wall?

• AThe growth of mold due to poor ventilation
• BA white, powdery deposit of soluble salts left on the wall surface as water evaporates
• CThe cracking of block joints due to earth tremors
• DA decorative rendering texture applied using a wooden float

What does the grade designation 'C20' for concrete signify in structural drawings?

• AA mix containing exactly 20% cement by weight
• BConcrete with a characteristic compressive cube strength of 20 N/mm² at 28 days
• CConcrete that must be cured for a maximum of 20 hours
• DA concrete mix containing 20mm aggregates only

Which geometrical method is used on-site to ensure that building corners are set out at a perfect 90-degree right angle?

• AThe 1:2:4 volume ratio method
• BThe 3:4:5 triangle rule (Pythagorean theorem)
• CThe vertical plumbing method
• DThe straight-line boundary method

What is the primary purpose of setting up profile boards during building layout operations?

• ATo provide storage space for masonry hand tools
• BTo record wall and foundation line positions using string lines and nail markers
• CTo serve as formwork shuttering for concrete floor slabs
• DTo protect the excavation trench from rainwater runoff