Safety, Codes, and Environmental Compliance
Core concepts
Safety questions center on hazard recognition and hierarchy of controls - elimination, substitution, engineering controls, administrative controls, then PPE as the last line. Know fall protection triggers and systems, excavation protective systems (sloping, shoring, shielding) and the competent person role, scaffold and ladder rules, hazard communication, and confined space entry.
Codes and environment: know permits (building, grading, NPDES), stormwater pollution prevention, hazardous waste handling, asbestos and lead precautions in renovation, and dust control. Arizona-specific concerns include heat illness prevention, wildfire risk, and water use restrictions.
Traps to watch
- Relying on PPE when an engineering control would eliminate the hazard.
- Entering an excavation without a competent-person inspection, especially after rain.
- Treating a confined space as safe because it "looks ventilated."
- Discharging washout or dewatering water to a storm drain.
- Skipping heat-acclimatization planning in summer months.
Rule of thumb
Apply the hierarchy top-down: can the hazard be eliminated, then engineered out, then administered, and only then worn. If your only answer is PPE, you have not finished thinking.
Worked example
A crew must work in a 6-foot-deep trench. PPE alone (hard hat, vest) does nothing against collapse. Correct control: a protective system (sloping, shoring, or shielding) designed for the soil type, plus a competent-person inspection before entry and after any rain event.