Environmental and Weather Hazards in Tree Care Flashcards

According to ANSI Z133, at what point must all tree climbing and aerial lift operations be suspended due to lightning risk?

Answer: When the 30-30 rule is triggered: lightning seen and thunder heard within 30 seconds

The 30-30 rule is the standard: if thunder is heard within 30 seconds of a lightning flash (meaning the strike is within 6 miles), all elevated work must stop immediately. Workers should seek substantial shelter and wait 30 minutes after the last thunder before resuming work. Elevated positions in trees or aerial lifts dramatically increase lightning risk.

Which early symptom combination should a crew leader recognize as a sign that a worker may be developing heat exhaustion during summer tree work?

Answer: Heavy sweating, pale or moist skin, weakness, and nausea

Heat exhaustion presents with heavy sweating, cool/pale/moist skin, weakness, dizziness, headache, and nausea. It is a serious warning that the body is losing its ability to cool itself. Immediate actions include moving the worker to shade, cooling with water, and hydrating. Heat exhaustion can rapidly progress to heat stroke if untreated.

A crew member is stung multiple times by yellow jackets while pruning a tree and immediately reports throat tightness and difficulty swallowing. What is the correct emergency response?

Answer: Recognize this as a potential anaphylactic reaction, call 911 immediately, and use an epinephrine auto-injector if available

Throat tightness and difficulty swallowing after multiple stings are signs of anaphylaxis — a life-threatening allergic reaction. This is a 911-level emergency. If the worker or the first aid kit has an epinephrine auto-injector (EpiPen), it should be used immediately. Antihistamines alone are not adequate treatment for anaphylaxis.

Under OSHA's heat illness prevention guidelines, which measure is considered the MOST effective primary control for reducing heat illness risk on an outdoor tree care crew?

Answer: Scheduling frequent rest breaks in shade and ensuring access to water every 15-20 minutes

OSHA's heat illness prevention program prioritizes the engineering and administrative controls of rest, shade, and water. Specifically: workers should have access to shade, drink about 1 cup of water every 15-20 minutes, and take regular cool-down rest periods. New workers especially need a gradual acclimatization schedule during the first 1-2 weeks of summer heat.

A crew is working in freezing temperatures and a worker reports that their fingers have become white, hard, and numb. What condition does this describe and what is the immediate field treatment?

Answer: Frostbite — protect the area from further cold and do NOT rub or rewarm in the field if refreezing is possible

White, hard, numb tissue is frostbite. Field rewarming is only appropriate if there is no risk of the tissue refreezing — refreezing thawed tissue causes far greater damage than leaving it frozen until definitive medical care is available. Rubbing frostbitten tissue causes mechanical damage to already-injured cells. The priority is protecting the area and evacuating to medical care.

Which ANSI Z133 provision governs the decision to suspend tree care operations due to high winds?

Answer: Climbing and aerial lift operations must be evaluated for suspension when wind conditions create a hazard to workers, and the qualified supervisor makes the call

ANSI Z133 does not set a single wind-speed threshold; instead it requires that a qualified supervisor evaluate conditions and suspend operations when wind creates unacceptable risk. Factors include wind speed, gusts, tree species, condition of the tree, and the work being performed. This judgment-based approach places clear responsibility on the supervisor.