Heat, hydration and sun

01The short version

Sources 12

Heat is the easiest way to have a bad day at an outdoor festival, and it is almost all preventable. Find shade. Drink water all day, not only when you feel dry. Pace yourself. Watch your friends as well as yourself.

DanceSafe, a harm reduction nonprofit, says heat, stress, low blood sugar and dehydration are probably the most common reasons people lose consciousness at shows.3

02How hot it really is

Sources 4

The temperature on your phone is not what your body feels. The National Weather Service uses the Heat Index, which adds humidity to air temperature. Its example is 96°F air at 65 percent humidity, which feels like 121°F.

There is a second catch. Heat Index values were built for shade and light wind. In full sun, the NWS says, they can run up to 15°F higher. A festival field with no trees is full sun.

The CDC runs a HeatRisk dashboard where you enter a ZIP code and get a forecast for the area. Check it for the festival's city the week before, then again the morning you leave.1

03Staying cool

Sources 15

The CDC advice for people outside for a long time is simple. Stay in the shade as much as you can. Take breaks. Do the hard things at the coolest part of the day or evening.

• Wear loose, lightweight, light-colored clothing, and sunscreen.
• Pace yourself. The CDC lists it as its own step.
• Take a cool shower or bath when you can. A hotel room is worth the money on a hot weekend.
• Check on a friend and ask them to check on you.

The CDC adds one detail. Sunburned skin releases heat more slowly, so a burn makes it harder to cool off. Sunscreen helps you stay cool as well as protecting your skin.

Our take. Treat the dance floor of a packed tent as its own heat zone. Step out for ten minutes when you start to feel heavy or dizzy. That is advice from people who have stood in them, not a number from an agency.

04Water

Sources 1

The CDC says to carry a water bottle and drink and refill it throughout the day. It says drinking water on hot days helps keep you hydrated whether or not you are active.

It also gives a plain check. If your urine is light yellow or clear, you are usually drinking enough. If it is darker than that, drink more.

The CDC says to consider limiting drinks high in sugar and sodium, caffeine and alcohol. At a festival that mostly means energy drinks, big sodas and the third beer in the sun.

Too much water can make you feel very unwell too. DanceSafe says heat illness, either dehydration or over-hydration, can feel bad enough to cause full panic attacks. The fix is steady sips all day, not a large amount at once.3

05Sun

Sources 6

The CDC says UV rays are strongest from 10 a.m. to 4 p.m. daylight saving time in the continental US. They reach you on cloudy days, and they reflect off surfaces such as water, cement and sand. A festival lot or a paved site is a lot of cement.

If the UV Index is 3 or higher where you are, the CDC lists these steps:

• Stay in the shade.
• Wear clothing that covers your arms and legs.
• Wear a hat with a wide brim to shade your face, head, ears and neck.
• Wear sunglasses that wrap around and block UVA and UVB rays.
• Use a broad-spectrum sunscreen with an SPF of 15 or higher.

If a hat and long sleeves are not practical, the CDC says to use plenty of sunscreen on all exposed skin, including the ears and the back of the neck. Put it on before you leave your hotel or car. The gate line is slow and you will be standing in it.

A tan is not a sign of health. The CDC says any change in skin color after UV exposure, a tan or a burn, is a sign of injury.

06The signs, and what to do

Sources 2

NIOSH, the CDC's workplace safety institute, writes these for workers. The body does not know the difference between a job site and a field in July, so the signs and first aid carry over.

At a festival, the clinic is the medical tent. Every festival page lists what we recorded about medical on site. Find the tent on your first lap and you will not be searching for it when you need it.

07Who has a higher risk

Sources 17

Anyone can get heat illness. The CDC lists people with asthma, people with heart disease, pregnant people, anyone 65 or older, and people working or exercising outside in the heat as groups that may need to take extra steps. Dancing all day in the sun is exercising outside.

Medicine matters too. The CDC says many medicines can make you dehydrated or overheated and some need to be kept out of hot places. Do not stop or change a medicine until you talk to your doctor. Do ask your doctor before the trip.

08A plan you can actually follow

1. 1
   The week before

   Check the HeatRisk forecast and the festival's weather notes. Ask your doctor about any medicine.

2. 2
   Before the gate

   Eat. Put on sunscreen. Wear a hat and light clothes. Bring an empty bottle that follows the bag policy.

3. 3
   First lap

   Find medical, free water and shade. Learn where the cool spots are.

4. 4
   All day

   Sip water. Take a break in shade every hour. Check on your group at a set time.

5. 5
   If you feel off

   Stop. Go to shade. Drink water. If it is not passing in a few minutes, walk to medical. Do not wait for it to get worse.

See camping 101 for night temperatures and storms, and the harm reduction guide for how heat interacts with other things.