The short answer
Carry more water than you think, drink before you are thirsty, rest in shade during the hottest hours, and learn the signs of heat illness. At high altitude, the air is dry, so keep drinking, and never leave a person or animal in a closed, parked car.
Do
- Plan around 4 litres per person per day, more in heat
- Drink steadily, and add oral rehydration salts on hot days
- Rest in shade in the hottest hours
- Wear a hat and light, loose clothing
- Watch each other for warning signs
Do not
- Wait until you are thirsty to drink
- Leave anyone in a parked car
- Push on when dizzy or confused
- Rely on alcohol or caffeine to keep going
- Skip salt and fluids when sweating a lot
How much to drink
- As a planning start, carry around 4 litres per person per day for drinking and basic cooking
- On very hot days, or in hard physical work, you may need more
- At high altitude, medical guidance suggests about 3 to 4 litres a day, because the air is dry and you breathe harder
- Drink little and often, instead of a lot at once
- Oral rehydration salts help replace what you lose in heavy sweat
Water is heavy. One litre weighs one kilogram, so water uses up much of a Jimny's payload. See overlanding setups.
Heat illness
| Stage | Signs | What to do |
|---|---|---|
| Heat cramps | Painful muscle cramps while hot and sweating | Rest in shade, sip fluids with salts, and stretch gently. |
| Heat exhaustion | Heavy sweating, headache, dizziness, nausea, weakness, cool and clammy skin | Move to shade, cool the skin, loosen clothing, and give small sips of fluid. |
| Heat stroke | Confusion, very hot skin that may be dry, collapse, fits | This is an emergency. Call 112, cool the person quickly with water and fanning, and do not give drinks if they are not alert. |
Heat stroke can be fatal. If someone has heat exhaustion and is not improving after a short while, treat it as serious.
Keeping cool
- Plan hard driving and walking for the cooler parts of the day
- Park in shade, and open the doors and windows to let the cabin cool before you get in
- Wear light, loose, light-coloured clothing, a hat and sunscreen
- Wet a cloth or a hat to help cool the neck
- Keep the fridge or a cooler for cold drinks, and keep drinks out of direct sun
Cars, children and animals
A parked car heats up quickly and can become deadly within minutes. Never leave a child, a person or an animal in a closed car, even for a short while. At camps, keep children and pets in shade, and watch them closely.
Pick the conditions
Tap the conditions to see how to stay safe.
Tap conditions (6 to try)
The plan for Hot day on the trail
- The plan
- -
- Details
- -
Common mistakes
- Waiting until you are thirsty. By then you are already behind.
- Underestimating the heat. Indian summers are severe.
- Ignoring altitude dryness. You still lose water in the cold.
- Leaving anyone in a parked car. It can be deadly within minutes.
- Pushing on when dizzy. Stop and cool down.
- Carrying too little water. Plan with a margin.
A final word. Heat illness and dehydration can kill. This guide is general information, not medical advice. If someone is confused, collapses or stops sweating in the heat, call 112 and cool them immediately.