Sri Lanka NVQ L3 Carpenter key terms

Items worn to reduce injury risk on site, such as safety boots, helmet, eye protection, gloves, hearing protection and high-visibility vest. Employers must supply suitable PPE free of charge where hazards cannot be controlled otherwise.

Ranked order for managing hazards: eliminate the risk, substitute, use engineering controls, apply administrative controls, then rely on PPE last. It guides decisions about guarding machinery, ventilation and safe systems of work on carpentry sites.

A written process that identifies hazards in a task, judges how likely and how severe harm could be, and records control measures and responsible persons before work starts. It must be reviewed when conditions change.

A short briefing held at the workplace before or during a shift to explain a specific hazard, safe method or lesson from an incident. Attendance is usually recorded so the employer can show the information was given.

A document describing the sequence of steps, plant, materials and controls used to carry out a defined work activity safely. It complements the risk assessment and is often required before high-risk tasks such as formwork erection.

Measures to keep airborne dust below exposure limits, including local exhaust ventilation at machines, dust extraction bags, wet sweeping or vacuuming, and respiratory protection where extraction is inadequate. Hardwood dust is a recognised carcinogen.

An extraction system that captures dust, chips or fumes close to the point of generation and removes them from the breathing zone. It must be inspected and tested at intervals, and records kept.

A shaped wooden or plastic hand tool used to feed short or narrow workpieces past a circular saw blade or spindle, keeping fingers well away from the cutting edge. It must be kept within reach at the machine.

A fixed blade mounted behind a circular saw blade, in line with the cut, that prevents the kerf closing and gripping the back of the blade. It reduces the risk of kickback on ripping operations.

The sudden violent ejection of a workpiece back towards the operator, caused when the blade or cutter grabs the material, for example through binding, poor fence alignment or feeding against rotation. It is a leading cause of serious saw injuries.

Work where a person could fall a distance liable to cause injury, including from ladders, scaffolds, roof edges and formwork. Falls must be prevented by suitable platforms, guardrails or fall-arrest systems, and access equipment must be inspected.

A rigid barrier, usually a top rail, intermediate rail and toe board, fixed around an edge or opening to stop people or materials falling. It must be strong enough to withstand expected loads and be securely fixed.

A formal written authorisation required before certain high-risk activities such as hot work, confined-space entry or work on live services. It records the precautions taken, the time limits and who authorised and received the permit.

A power saw with a toothed circular blade used for straight cross-cutting and ripping of timber and sheet materials. Safe use requires a sharp blade, correct depth setting, a secure fence and guarding.

A measuring and marking tool comprising a steel rule with a sliding stock that can be set at 90 degrees or 45 degrees. It is used to mark square lines, check right angles and set out joints.

A fixed square with a blade set permanently at 90 degrees to a thicker stock, used for checking and marking right angles on timber and assembled work. It should be checked against a known straight edge for accuracy.

A tool with a sliding stock and a sharp pin or cutting wheel that scores a line parallel to an edge at a set distance. It is used to mark mortise and tenon shoulders, rebates and joint depths.

A straightedge containing sealed vials of liquid with an air bubble, used to check whether a surface is horizontal or vertical. Long levels are used for setting out, levelling wall plates and aligning door frames.

Timber from broad-leaved trees, generally denser and more durable than softwood, used for structural members, flooring, doors and furniture. Examples include teak, mahogany, meranti and jackwood; the term describes the tree type, not necessarily hardness.

Timber from coniferous trees such as pine, fir, spruce and cypress, widely used for framing, formwork and joinery. It is usually lighter and cheaper than hardwood, and grades are commonly specified by strength class.

The mass of water in timber expressed as a percentage of its oven-dry mass. It affects strength, shrinkage, movement and gluing; timber should be dried close to the moisture content of its final service environment.

The controlled drying of timber, either in air or in a kiln, to reduce moisture content before use. Proper seasoning limits shrinkage, warping, splitting and decay, and improves dimensional stability in joinery.

The reduction in timber dimensions as it loses moisture, which is greater across the grain than along it. Uneven shrinkage causes cupping, bowing and splitting, and must be allowed for in wide boards and panel work.

A sheet material made from thin layers of veneer glued together with the grain direction of adjacent layers at right angles. This cross-lamination gives good strength and dimensional stability, and it is used for sheathing, boxing and formwork linings.

A panel product made by breaking down wood fibres and pressing them with resin into uniform, smooth sheets. It machines and paints well but swells badly when wet and produces fine dust when cut.

A panel made by pressing wood chips or flakes with adhesive into a flat sheet. It is inexpensive and used for flooring substrate and carcass work, but has low screw-holding strength at edges and poor moisture resistance unless specially treated.

Application of chemicals to timber to resist insects, fungi and moisture damage, by brushing, dipping or pressure impregnation. Treatment is specified for timber in contact with ground, masonry or damp conditions.

The process of transferring dimensions and levels from drawings to the site or workpiece, establishing lines, squares and reference points before construction begins. Errors at this stage multiply through all later work.

A fixed reference point or level from which other heights and positions are measured. A datum is marked clearly and protected so that all subsequent setting out remains consistent across the works.

A setting-out technique for establishing a right angle using a triangle with sides in the ratio 3:4:5, which satisfies Pythagoras' theorem. Multiples of these lengths allow large square corners to be set out on site.

The ratio between a dimension on a drawing and the real dimension it represents, for example 1:50 or 1:100. Choosing an appropriate scale allows sufficient detail to be shown on a readable sheet size.

A detailed, dimensioned drawing that gives the builder enough information to construct an element, including sizes, materials, positions and references to specifications. It must be the current approved revision before work proceeds.

The temporary mould, usually of timber or plywood panels with framing and supports, that holds wet concrete in the required shape until it gains sufficient strength. It must be strong, rigid, accurate and easy to strike.

The face panels of a formwork assembly that directly contact and shape the concrete surface. Their quality, tightness and cleanliness determine the finish and accuracy of the cast element.

Adjustable vertical supports and diagonal members that carry formwork loads down to a firm base and prevent sideways movement. They must be plumb, adequately founded and braced in both directions.

A liquid or grease applied to shuttering faces to stop concrete bonding to them, making striking easier and protecting the panel surface. It must be compatible with the concrete finish required and not stain the surface.

The angle of a roof slope, expressed in degrees or as a ratio of rise to run. Pitch governs covering choice, headroom, drainage and the geometry used to calculate rafter lengths.

A sloping structural member spanning from the wall plate or ridge to support the roof covering and transfer loads to the walls. Common rafters are parallel; hip and valley rafters occur at intersections.

The horizontal member at the apex of a roof against which the top ends of opposing rafters abut. It helps align the rafters and stiffens the roof structure along its length.

A joint in which a projecting tenon on one member fits into a matching rectangular mortise cut in another, usually secured with wedges, pegs or adhesive. It resists racking and is common in door frames and furniture.

A joint using flared, wedge-shaped pins and tails that interlock, giving strong resistance to being pulled apart in one direction. It is used in drawer construction and box work where tensile strength is needed.

A step-shaped recess cut along the edge or end of a member so that another component, such as a glass pane or panel, can sit flush within it. Rebates are common in window sashes and door frames.

Short horizontal pieces of timber fixed between studs or joists to stiffen the frame, provide a fixing for board edges and help restrict the spread of fire and smoke within a partition.

A non-loadbearing internal wall built from vertical timber studs, usually at fixed centres, with a head and sole plate and covered by board or lath. Services can be run within the cavity.

A horizontal structural member, usually repeated at regular centres, that supports a floor or ceiling. Joist size, spacing and span are governed by the loads and by the flooring or ceiling material above.

A horizontal member that supports the ceiling lining and ties opposing rafters together, helping resist the outward thrust of a pitched roof. It may also carry insulation and light fittings.

A document listing measured items of work with descriptions and quantities, prepared from drawings so that work can be priced and compared consistently. It also forms a basis for valuing variations and progress payments.

The process of measuring quantities of work from drawings and entering them in a structured order, applying rules for what is included or deducted. Accurate take-off depends on correct reading of dimensions and scales.

An extra percentage added to the net measured quantity of a material to cover cutting losses, defects, breakage and offcuts. The allowance varies with material, complexity of the work and site conditions.

Labour time spent on activities that do not form part of the permanent work, such as setting up, moving materials, cleaning and striking formwork. It must be included when planning realistic durations and costs.

A record of defects or incomplete items found during inspection before handover, each with a location and description so it can be corrected. Signing off the list confirms the work is acceptable.

A written direction from the authorised person, such as the engineer or site supervisor, requiring a change or clarification to the work. It should be recorded and acknowledged so that its cost and time effects can be tracked.