Fire Safety, Chemical Safety and Environmental Protection
Fire: the triangle and the strategy
The fire triangle (fuel, oxygen, heat) plus the uninhibited chain reaction explains suppression. Know the fire classes (A solids, B liquids, C gases, D metals, F cooking oils, and electrical) and match extinguisher media correctly - water on burning metal or live electrical equipment is a classic trap. Fire strategy covers prevention (housekeeping, ignition control, storage separation), detection and alarm, means of escape (travel distance, exits, signage, lighting), compartmentation, and emergency lighting. Distinguish flammable (flash point below the threshold) from combustible, and know that flash point and auto-ignition temperature are different properties.
Chemical safety
The core is the SDS (16-section format) and the hazard communication chain: label, pictogram, signal word, hazard and precautionary statements. Controls follow the hierarchy, with substitution and engineering controls/ventilation preferred over PPE. Storage requires segregation by compatibility (oxidiser vs flammable vs acid), secondary containment, and inventory control. Spill response needs absorbents, PPE, and disposal routes.
Environmental protection
Cover waste segregation and duty of care, hazardous waste manifests, emissions and effluent limits, spill prevention (bunding, drainage protection), and the polluter-pays principle. Traps: treating dilute chemical waste as non-hazardous, and forgetting that a firewater runoff can be an environmental incident.
Rule of thumb
For any chemical question, the first control is eliminate or substitute the substance; if it stays, the answer is engineering control plus SDS-based PPE, never PPE alone.