Basic Safety
Hazard recognition first
Safety begins with a hazard assessment before the task starts: look up for overhead loads and power lines, look down for trip and fall hazards, and look around for chemical, electrical, and struck-by risks. PPE is the last line of defense, not the first. Typical site PPE includes a hard hat, safety glasses with side shields, hearing protection, work gloves, safety-toe boots, and high-visibility clothing. Hard hats are classified by electrical protection: Class A (up to 2,200 V), Class B (up to 20,000 V), and Class C (conductive, no electrical protection).
Numbers that get tested
Fall protection in construction is triggered at 6 feet; on scaffolds at 10 feet; in general industry at 4 feet. Questions routinely swap these. Excavations 5 feet or deeper require a protective system and a competent person. Temporary power must be GFCI protected. Under lockout/tagout, only the person who applied a lock may remove it. Never remove or bypass a guard, and always report near misses, not just injuries. Know the SDS location and the emergency action plan.
Worked rule of thumb: ladder setup
The 4:1 rule says the base sits 1 foot out from the wall for every 4 feet of working height, and the ladder must extend 3 feet above the landing. A 20-foot working height means the base is 20 ÷ 4 = 5 feet from the wall. Maintain three-point contact and face the ladder.