father and son talking by phone on hot day, with son reminding father to use air conditioning. Text reads Be a Buddy! When it's hot, make sure neighbors and family are in an air-conditioned place.

Extreme Heat and Your Health

COVID-19: Air Conditioning and Open Windows

The virus that causes COVID-19 will not enter your home through an air conditioner or an open window.

The virus is usually spread to people who are in close contact (within about 6 feet) with a person who has COVID-19. It is spread through droplets that are sprayed when a person coughs or sneezes, and possibly when they sing or talk.

If someone with COVID-19 is in your home, opening the windows can increase air circulation. That may help stop the spread of COVID-19 by reducing the amount of virus in the air, but during heat waves, opening windows is not enough to keep cool.

Hot and humid summer weather can cause heat illness and even death. More Americans die from heat waves than all other natural disasters combined. In New York City, more than 80% of heat stroke deaths in recent years involved victims who were exposed to heat in homes without air conditioning. Those most vulnerable to extreme heat include older adults, people with chronic medical conditions or mental health conditions and the socially isolated.

Talk to your doctor about how to prevent heat illness during hot and humid weather. If you don't have a doctor, call 311 to find a doctor or clinic nearby.

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about staying safe in the heat.



Tips to Beat the Heat

Check the Weather Reports

Pay attention to weather reports on the news, or check National Weather Service reports. The heat index is a measure of how hot it feels based on temperature and humidity. A heat index above 95 degrees F is especially dangerous for older adults and other vulnerable individuals.

Keep Cool

The best way to prevent heat illness is to stay in an air-conditioned place. Make sure you and your family stay cool during a heat wave. If you or someone you know cannot stay cool at home, visit a cool place, such as a library, a friend's home with air conditioning or a city cooling center. Cooling centers are open across the city during serious heat waves. You can find a cooling center online or by calling 311.

The Cooling Assistance Program provides a limited number of air conditioners for people who meet income criteria and have written letter from a health care provider documenting an increased risk for heat-related illness. For more information, including how to apply, call 311.

Check on Neighbors and Family Members

Check on vulnerable family, friends, and neighbors to make sure they stay safe and cool. Air conditioning is the best way to keep cool when it is hot outside, but some people do not have an air conditioner or do not turn it on when they need it. Encourage them to use air conditioning. Help them get to an air-conditioned place if they cannot stay cool at home.

Heat Illness

Heat illness occurs when the body cannot cool down. The most serious forms of heat illness are heat exhaustion and heat stroke. Heat stroke occurs when the body's temperature rises quickly. It can rapidly lead to death.

Keeping cool can be hard work for the body. This extra stress on the body can also worsen other health conditions such as heart and lung disease.

Signs of Heat Illness

If you or someone you know has the following symptoms of heat illness, call 911 or go to an emergency room:

  • Hot, dry skin, or cold, clammy skin
  • Confusion, hallucinations and disorientation
  • Loss of consciousness or unresponsive
  • Nausea or vomiting
  • Trouble breathing
  • Rapid, strong pulse
  • Weakness
  • Dizziness

If you or someone you know has the following warning signs that they may be at risk for heat illness, get to a cool place, remove extra clothes, and drink lots of water:

  • Heavy sweating
  • Muscle cramps
  • Lightheadedness, feeling faint
  • Headache
  • Decreased energy
  • Loss of appetite, nausea

People Most At Risk for Heat Illness

You are more likely to get sick from heat if you:

  • Are 65 years or older
  • Have chronic medical conditions, such as heart disease, diabetes or obesity
  • Have mental health conditions, such as dementia or schizophrenia
  • Take certain medications that affect the body's cooling mechanisms — talk to your doctor for more information and advice
  • Use drugs or drink heavily
  • Are socially isolated, have limited mobility or are unable to leave the house

Prevent Heat Illness Indoors

In addition to following our Beat the Heat tips above, when it is hot in your home:

  • In extreme heat, a fan alone may not provide enough cooling. If you use a fan, use it only when the air conditioner is on or when the windows are open.
  • Close window shades or curtains to keep the sun out of your home.
  • Try not to use your stove and oven.
  • Take a cool shower or bath using tepid water. Sudden temperature changes may make you feel dizzy or sick.
  • Drink plenty of water on hot days, even if you are not thirsty.
  • Avoid drinks with alcohol, caffeine or lots of sugar.
  • Prevent Heat Illness Outdoors

    People who work or exercise outdoors are at higher risk of becoming dehydrated and developing heat-related illness. On hot days, be sure to:

    • Avoid strenuous physical activity.
    • Drink plenty of water, even if you are not thirsty.
    • Stay in the shade and out of direct sun.
    • Wear light, loose-fitting clothes.
    • Use a hat to protect your face and head.
    • Wear sunscreen with at least an SPF of 15.
    • Limit outdoor activities to early morning and late evening hours.
    • Avoid drinks with alcohol, caffeine or sugar.

    If your work outdoors regularly:

    • Drink water every 15 minutes.
    • Take frequent rest breaks in shaded or air-conditioned areas.
    • Wear lightweight, light colored, loose-fitting clothing if possible.
    • Be alert for the signs of heat illness in yourself and in your colleagues.

    Additional Resources

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