Lightning & Thunderstorm Safety

Lightning kills approximately 2,000 people worldwide every year and injures many times more. Unlike many natural hazards, lightning strikes are highly survivable — nearly 90% of people struck by lightning survive. What separates survivors from fatalities is almost always the decision to seek safe shelter and the speed of first aid response.

Lightning can strike the same location multiple times. It can strike from a storm that is still 15 km (10 miles) away. It can strike with clear skies visible overhead. Understanding the real nature of lightning risk changes the decisions you make outdoors.

Understanding Lightning Risk

Lightning follows the path of least electrical resistance to the ground. This means:

Location	Risk Level	Why
Under a tall isolated tree	Extremely high	Tree provides elevated conduction path
Open field or hilltop	Extremely high	Your body is the highest point
Near water (lake, river, beach)	Very high	Water conducts; open terrain; swimming = direct contact
Under a small shelter or picnic shed	High	Lightning can jump from shelter to nearby objects including people
In a vehicle (metal-bodied car)	Low	Acts as a Faraday cage — electricity flows around the outside
Inside a substantial building	Very low	Proper lightning protection and grounding

⚠️ The "30-30 rule": If the time between lightning flash and thunder is 30 seconds or less, the storm is within 10 km (6 miles) — seek shelter immediately. Wait 30 minutes after the last thunder before returning outdoors.

Before a Thunderstorm

1. Check weather forecasts before any outdoor activity — afternoon thunderstorms are common in tropical and temperate climates, especially in summer.
2. Identify your shelter options before you need them: a substantial building with plumbing and wiring, or a hard-topped metal vehicle.
3. Do not start outdoor activities that would be difficult to interrupt quickly (swimming, boating, climbing) when storms are forecast.
4. If caught far from shelter, identify escape routes and low ground away from trees, hilltops, and water.

Seeking Safe Shelter

What Counts as Safe Shelter

Shelter Type	Safe?	Notes
Substantial enclosed building (house, school, office)	Yes	Best option — move inside immediately
Hard-topped metal vehicle (car, bus, truck)	Yes	Second best — keep windows up
Open structure (picnic shelter, bus stop, tent)	No	Provides no protection from lightning
Under a tall tree	No	Extremely dangerous — never do this
Cave	Partial	Safe inside but dangerous at the entrance due to ground current

When Caught Outdoors With No Shelter

If you cannot reach safe shelter before the storm:

1. Get away from tall isolated trees, hilltops, bodies of water, and open fields.
2. Find a low-lying area away from standing water — a ravine or hollow.
3. Lightning crouch: Crouch low on the balls of your feet, feet together, head lowered and ears covered, arms wrapped around knees. This minimises your profile and contact with the ground. Do NOT lie flat (increases ground current exposure).
4. Spread out from other members of your group — keep at least 15 metres (50 feet) between people. This way, a single strike cannot incapacitate the whole group and survivors can give first aid.
5. Remove metal-framed backpacks and avoid holding metal objects.

⚠️ Do not shelter under tall isolated trees. This is the leading cause of lightning fatalities globally. A lightning strike in a tree creates a "ground current" that can electrocute anyone within 10 metres (30 feet) of the base.

Inside Buildings and Vehicles

In a Building

1. Stay away from windows, doors, and porches.
2. Do not touch plumbing (showers, sinks, pipes) during a storm — lightning can travel through water pipes.
3. Do not use corded (wired) phones — lightning can travel through telephone wires.
4. Unplug electronic equipment to protect from power surges — or use surge protectors.
5. Avoid contact with electrical equipment such as computers and TVs.

In a Vehicle

1. Pull over and park — driving in a thunderstorm reduces your reaction time and the storm may be producing hail.
2. Keep windows closed.
3. Do not touch metal parts of the car interior during a strike.
4. The tyres provide no protection — the metal body of the car channelling current to the ground is what protects you.

If Someone Is Struck by Lightning

⚠️ It is safe to touch a lightning strike victim. The body does not retain electrical charge after a strike — there is no risk to rescuers.

Immediate Response

1. Call emergency services immediately.
2. Move the person to safety if there is ongoing storm risk.
3. Check for breathing and pulse — lightning victims often experience cardiac arrest, and immediate CPR dramatically improves survival.
4. Begin CPR if the person is not breathing and has no pulse — continue until emergency services arrive.
5. Treat burns: lightning strikes cause entry and exit burns. Cover burn areas with a clean dry dressing if available.
6. Monitor for shock — keep the person warm and lying down.

Common Effects of Lightning Strike

• Cardiac arrest (most common cause of lightning death)
• Respiratory arrest
• Burns at entry and exit points
• Ruptured eardrums (from thunder close to the strike)
• Eye damage (temporary or permanent)
• Neurological effects (memory loss, personality changes, chronic pain)
• Blunt trauma from the force of the strike

Water Safety and Lightning

• Exit water immediately when you hear thunder — water is an excellent conductor.
• In open water, a person's head and torso become the highest point — extreme risk.
• On a boat: go below deck or into the cabin, stay away from metal, do not touch the engine.
• Even after the storm, wait 30 minutes after the last thunder before returning to swimming or boating.

Groups at Higher Risk

Group	Risk Factor
Agricultural workers	Long hours outdoors in open fields
Hikers and climbers	Elevated terrain, limited shelter options
Golfers	Open terrain, holding metal clubs
Beach visitors	Open water, flat terrain
Construction workers	Elevated work, metal structures
Campers	Tents provide zero protection

Quick Reference — Lightning Safety

Situation	Action
See lightning or hear thunder	Seek shelter immediately — if thunder audible, you are at risk
No shelter available outdoors	Low crouch in hollow, away from trees and water, spread group out
In a substantial building	Avoid windows, plumbing, and corded devices
In a metal car	Stay inside, windows up, park if possible
Under a tall tree	Move away immediately — most dangerous outdoor location
Someone is struck	Call emergency services, begin CPR if no pulse/breathing
After last thunder	Wait 30 minutes before returning outdoors

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This guide is for general preparedness education. In a medical emergency, call local emergency services immediately. Lightning risk varies by terrain and region — consult local weather services for area-specific guidance.