Heat, Cold & Environmental Hazards

The weather is a real jobsite hazard — and a deadly one.

Heat

Heat illness (cramps, exhaustion, and life-threatening heat stroke) is preventable with water, rest, and shade, and letting new workers acclimatize. Learn the warning signs and act fast.

Cold

Hypothermia and frostbite — dress in layers, stay dry, and take warm breaks.

Other

• Sun / UV — long-term skin risk; cover up.
• Lightning / storms — stop work and take shelter.

Going Deeper (Intermediate)

The environment itself is a hazard. Heat illness progresses: heat rash → cramps → heat exhaustion (heavy sweat, nausea, weakness) → heat stroke (hot/dry or wet skin, confusion, medical emergency — call 911, cool aggressively). Prevention is Water, Rest, Shade plus acclimatization — new/returning workers ramp up exposure over ~1–2 weeks (most heat deaths are in the first days).

Advanced / Pro-Level

Round out the environmental hazards:

• Heat metrics: schedule by heat index / WBGT; build in a work/rest ratio and a buddy system to watch for symptoms. OSHA enforces heat under the General Duty Clause (plus a National Emphasis Program).
• Cold stress: hypothermia (shivering → confusion) and frostbite (white/waxy skin) — layer, stay dry, warm breaks, watch wind chill.
• Other: UV (skin cancer — cover/sunscreen), lightning (30-30 rule, shelter), insects/poisonous plants/wildlife, and air quality (wildfire smoke).
• The fix is mostly administrative: acclimatize, hydrate, schedule around extremes, train supervisors to spot early signs, and have an emergency response ready.

Practice Challenge

A new laborer on a 95°F day becomes confused and stops sweating. What is this, and what are the first actions? (Answer: likely heat stroke — a life-threatening emergency: call 911, move to shade, cool aggressively (ice/water, fan), and stay with them. Note he's not acclimatized — a key risk factor.)

In Practice

A new worker, not yet acclimatized, pushes through a hot afternoon and collapses with heat stroke — a medical emergency. Water, rest, shade, and acclimatization prevent it.

Common Mistakes to Avoid

• Not letting new workers acclimatize to heat
• Ignoring early heat-illness warning signs
• Working through lightning instead of taking shelter

Takeaway: Beat heat with water-rest-shade and acclimatization; dress for cold; cover up from the sun; and stop work for lightning.

⚠️ Educational overview — NOT official OSHA certification. Get formal training from an authorized trainer and follow current OSHA standards (29 CFR 1926) and your employer's program.