Safe Work Practices and Occupational Health and Safety
The Safe Work Practices and Occupational Health and Safety domain tests whether you can recognize hazards specific to a toolroom and apply the correct control before work starts. Questions commonly target lockout, abrasive wheels, press and crane safety, chemical handling, and the hierarchy of controls.
Hierarchy of controls and lockout
Controls rank from most to least effective: elimination, substitution, engineering controls, administrative controls, then PPE. PPE is the last line, not the first answer. For lockout, isolate every energy form - electrical, pneumatic, hydraulic, gravity, stored springs, thermal, and residual pressure in accumulators. Each worker applies a personal lock and tag; verify zero energy by attempting a start and by gauging pressure. Never rely on a stop button or a colleague's word.
Abrasive wheels and machine guarding
Ring-test vitrified wheels before mounting. The wheel rating must meet or exceed spindle speed. Keep the work rest within 3 mm (1/8 in) of the wheel and the tongue guard within 3 mm; these gaps are examined because a gap that is too large lets work pull into the wheel. Do not grind on the side of a straight wheel unless it is rated for it. On drill presses and mills, remove the chuck key, clamp the work, and clear chips with a brush, not a rag.
Presses, cranes and material handling
A press ram must be blocked mechanically before anyone reaches into the die space. Overhead crane capacity applies to the load and to the sling angles: tension per leg rises sharply as the included angle opens.
Chemicals and housekeeping
WHMIS/GHS labels carry six required elements; the SDS has 16 sections and section 4 covers first aid. Cutting fluid mist, carbide grinding dust containing cobalt, and solvent vapour require local exhaust ventilation.
Worked example
A 900 kg load is lifted with a two-leg sling at a 90° included angle. Tension per leg = W ÷ (2 cos 45°) = 900 ÷ 1.414 = 636 kg. If the same load is rigged at 120°, each leg sees 900 ÷ (2 cos 60°) = 900 kg - a 41% increase that can exceed a sling rated at 750 kg per leg. The correct exam answer is to reduce the angle or use a stronger sling; adding a third leg does not reliably reduce tension.
Traps
Choosing PPE as the primary control; forgetting stored hydraulic energy; assuming a guard gap of 10 mm is acceptable; confusing SDS sections with label elements; and treating a tag as a substitute for a personal lock.