Occupational Health, Safety and Environment on Site
Safety questions in the CTVET Certificate II paper are scenario-based: you are given a small blocklaying or concreting job and asked what could go wrong and what you would do about it. Marks go to candidates who name the hazard, name the control, and say what is recorded or inspected. Ghanaian law sets the frame - the Factories, Offices and Shops Act 1970 (Act 328) and the Labour Act 2003 (Act 651) both place a duty on the employer to provide a safe workplace and on the worker to follow safe systems.
Hazard recognition
- Falls from edges, openings and scaffold platforms - the biggest killer in blockwork.
- Manual handling: a 450 × 225 × 150 mm sandcrete block weighs about 17–20 kg, so 200 blocks in a day means over three tonnes moved by hand.
- Wet cement is caustic (pH around 12–13) and causes burns and dermatitis.
- Respirable silica dust from cutting, chasing and grinding blocks.
- Trench collapse during strip-footing excavation.
- Site traffic, reversing mixers and dumpers; 230 V hand tools and damaged extension leads.
- Heat stress and dehydration in the dry season.
Hierarchy of control
Work down the list before reaching for PPE: eliminate the hazard (hoist instead of carry), substitute (use lighter 100 mm blocks or a pump), engineer it out (guardrails, hoists, water dust suppression), control administratively (rotation, permits, toolbox talks), and only then rely on PPE - helmet, boots, gloves, goggles, dust mask, hi-vis, harness.
Scaffold and excavation rules
A working platform must be fully boarded, at least 600 mm wide, with a guardrail near 1.0 m, an intermediate rail and 150 mm toe boards. Scaffold is tied to the structure and inspected before first use, weekly, and after storms. Never support a platform on blocks or bricks. Shore or batter any trench deeper than 1.2 m, keep spoil at least 1 m back from the edge, provide a ladder, and inspect daily after rain.
Worked example
A mason must move 150 blocks to a first-floor slab 3.5 m up. Carrying them up a ladder is the hazard, so eliminate it: a gin wheel or materials hoist with a rated rope and a secured landing bay. If no hoist exists, engineer it - a properly erected tower scaffold with boarded platform and guardrails, blocks landed by rope in a bucket, never thrown or balanced on a shoulder up a ladder. PPE and training only control what remains.
Traps that cost marks
Answering “wear gloves and be careful”; treating PPE as the first control; confusing a hazard (the block) with the risk (a strained back); omitting inspection records and first-aid arrangements; ignoring dust, noise and spoil disposal affecting neighbours.