Occupational Health, Safety and Environment
This domain tests legal duties, workshop hazards, control measures and environmental responsibility. Answers score when they name the hazard, rank the control and quote a limit.
Legal framework
Cyprus Safety and Health at Work Law 89(I)/1996 and its regulations set employer duties: risk assessment, training, free PPE, consultation, accident reporting and health surveillance. Employees must follow controls and report hazards. Risk assessment is five steps: identify hazards, decide who is at risk, evaluate and prioritise, record, review.
Principal hazards
- Wood dust: hardwood dust is carcinogenic (IARC Group 1). Typical 8-hour exposure limits are 3 mg/m3 for hardwood and 5 mg/m3 for softwood. Dust also causes asthma, dermatitis and fire risk.
- Noise: lower action value 80 dB(A), upper 85 dB(A) with hearing protection mandatory; peak action value 135–137 dB(C).
- Hand-arm vibration: action value 2.5 m/s2 A(8), limit 5 m/s2.
- Chemicals: lacquers, thinners and adhesives - flammable, narcotic, sensitising; consult the safety data sheet.
- Machinery: guarding, interlocks, braking, push sticks; gloves are not worn near rotating shafts because they can be dragged in.
- Electrical: 30 mA RCD, portable appliance testing, 110 V on site.
- Fire and explosion: dust clouds and solvent vapour; housekeeping, extraction, hot-work permits.
- Manual handling, slips, sharp edges, stacked boards falling.
Control hierarchy
Eliminate → substitute → engineering controls (local exhaust ventilation, guarding) → administrative controls (training, rotation) → PPE last.
Ventilation numbers
Capture velocity at the hood 0.5–1 m/s; transport velocity in the duct about 20 m/s so chips do not settle.
Environment
Waste hierarchy: reduce, reuse, recycle, recover, dispose. Segregate offcuts, sawdust (biomass), finishes and rags as hazardous waste. Choose formaldehyde class E1 boards, certified timber (FSC/PEFC) and low-VOC finishes; keep the extractor filter maintained.
Worked example
A 100 mm duct must carry dust at 20 m/s. Area = π × 0.05² = 0.00785 m2. Flow = 0.00785 × 20 = 0.157 m3/s = 9.4 m3/min = 565 m3/h. If the extractor is rated 1000 m3/h free air, the resistance of the hood, duct and filter will reduce the actual flow, so the fan curve must be checked before assuming the machine is adequately extracted.
Traps that cost marks
Listing PPE as the first control; assuming a dust mask works over a beard; blowing dust off with compressed air; ignoring hardwood dust after sweeping; extracting machines but not hand sanding.
Rank controls in order and quote a number to prove the point.
Measurement, Costing and Quality Control
This domain tests the commercial and metrological side of the trade: correct instruments, tolerances, cost build-up, price setting and inspection. The classic marks are won or lost on markup versus margin.
Measuring instruments
- Steel rule 0.5 mm, tape measure ±1 mm, vernier caliper 0.02 mm, micrometer 0.01 mm, dial indicator 0.01 mm, feeler gauge for gaps.
- Accuracy is closeness to true value; precision is repeatability. Calibration checks both.
- Squareness: check diagonals - equal diagonals mean a true rectangle. Use an engineer's square for 90°.
- Zero the caliper before use; avoid parallax by reading square-on; do not measure at an angle across a chamfer.
- Joinery tolerance typically ±0.5 mm; machine setting and jig work often ±0.2 mm.
Reading a vernier
Main scale 12 mm plus the 13th vernier line coinciding on a 0.02 mm scale gives 12 + (13 × 0.02) = 12.26 mm.
Costing
- Direct material (including waste allowance), direct labour (hours × rate), direct expenses, then overheads (often 15–25%), then profit, then VAT at 19% in Cyprus on the selling price.
- Markup is a percentage of cost: price = cost × (1 + markup). Margin is a percentage of price: price = cost / (1 − margin). They are not the same number.
- A quotation is a fixed offer; an estimate is a prediction. Always state what is included, lead time and payment terms.
Quality control
Incoming inspection of boards (thickness, MC, defects), first-off inspection after setting, in-process checks (dimensions, squareness, joint gaps), final inspection against the drawing. Use checklists, record defects, apply corrective action, and treat rework as a cost of poor quality.
Worked example
A wardrobe: 2 sheets of board at €38 = €76.00; 22 m of edging at €0.90 = €19.80; fittings €24.50; 7.5 hours at €18 = €135.00. Direct cost = €255.30. Overheads 15% of direct = €38.30, so total cost = €293.60. With 20% markup: €293.60 × 1.20 = €352.32. With 20% margin: €293.60 / 0.80 = €367.00. The difference is €14.68 on a single job. VAT at 19% is then added to the selling price only: €367.00 × 1.19 = €436.73.
Traps that cost marks
Confusing markup with margin; forgetting waste and consumables; applying VAT to cost instead of to the selling price; comparing quotes with different specifications; measuring once; ignoring caliper zero error; inspecting only at the end.
Write the formula, then substitute - that is where the marks live.