Occupational Health and Safety, and Environmental Protection
This domain tests how you recognize hazards before they cause injury, apply the hierarchy of controls in the right order, handle hazardous products correctly, and keep site work from damaging the environment. Expect questions on legislation, WHMIS 2015, confined spaces, silica and asbestos, spill response, and erosion control.
Legal duties and worker rights
- OHS legislation is provincial or territorial on most sites; federally regulated projects fall under the Canada Labour Code.
- Workers have the right to know about hazards, the right to participate in health and safety, and the right to refuse work they believe is unsafe.
- Employers must provide hazard assessments, training, supervision, and PPE. Workers must follow procedures, inspect tools, and report hazards and incidents.
- Joint health and safety committees or worker representatives take part in inspections and incident investigations.
Hazard assessment and the hierarchy of controls
- Complete a field level hazard assessment (FLHA) at the start of each task and repeat it when weather, crew, or scope changes.
- Apply controls in order: eliminate, substitute, engineer out (guards, ventilation, shoring), administrative controls (procedures, rotation, signage), and PPE last.
- Recurring hazards: respirable silica from cutting concrete or block, asbestos in pre-1990 buildings, lead paint, mould, noise, heat and cold stress, and overhead power lines with provincial limits of approach.
WHMIS 2015 and confined spaces
- Supplier labels carry pictograms, signal words, and hazard statements; decanted products need workplace labels.
- The safety data sheet has 16 sections; Section 8 covers exposure controls and personal protection, Section 4 covers first aid.
- Confined space entry needs a hazard assessment, permit, atmospheric testing (oxygen between 19.5% and 23%), a standby attendant, and a rescue plan.
Environmental protection
- Install erosion and sediment controls such as silt fence, catch basin protection, and a rock construction entrance before grading starts.
- Keep a spill kit on site, use drip trays under equipment, and refuel well away from watercourses and storm drains (commonly 30 m).
- Segregate waste into clean fill, concrete, metal, wood, and hazardous streams; report spills to the regulator.
Worked example
A crew must cut concrete block for a foundation. The FLHA identifies respirable crystalline silica as the main hazard. Controls in hierarchy order: substitute pre-cut units where possible; use a wet saw with water suppression or a dust collector; barricade the cutting area with signage; issue at least an N95 respirator plus eye and face protection. The supervisor confirms the water supply is connected and records the controls and the re-assessment trigger on the FLHA before cutting begins.
Traps that cost marks
- Choosing PPE first instead of last in the hierarchy.
- Completing one FLHA in the morning and never updating it.
- Assuming a product needs no SDS because it is a common solvent.
- Treating sediment control as optional on small jobs.