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Extreme Heat

ALWAYS CALL 911 if you are in immediate danger and need emergency help.

Individuals, communities, and businesses can plan for and reduce the effects of extreme heat. Keep yourself and your family cool when the thermometer tops out. Check weather alerts and warnings from the National Weather Service.

Prepare for extreme heat


! EPA Warning: Recharging air conditioners with the wrong refrigerant poses injury and fire risks. Do not recharge or use a propane-based refrigerant such as "22a" in any air conditioner that is not designed to use propane or flammable refrigerants.
Read more about the danger and what you can do.
General information about unacceptable substitute refrigerants

Communities - adopt development strategies to reduce heat islands and coordinate local efforts:

Urban and suburban areas can be "heat islands," a zone 2-10 degrees F warmer than the surrounding rural countryside. Because they are warmer, heat islands use more energy to keep cool, which raises costs and reduces air quality. Communities can invest in long-term strategies such as:

  • Promoting or installing cool or vegetated "green" roofs
  • Planting more trees and vegetation
  • Switching to cooler paving materials.

Cities are increasingly starting heat wave response programs that coordinate efforts among local agencies and alert residents. Common examples of "best practices" include:

Offices, businesses, and other work sites - inform staff how to work safely and take steps to reduce energy demands:

Heat-induced occupational illnesses, injuries, and reduced productivity can occur in a hot work environment. More information how to prepare ahead for work-related heat stress (from National Institute for Occupational Safety and Health)

Building owners can follow five steps to save energy in summer:

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During extreme heat

Today's AQI forecast USA map. Click for summary info.

Check air quality where you live - hot weather can worsen ozone levels and other types of air quality.

CALL 911 in case of heat-related illness - heat stress, heat exhaustion or HEAT STROKE can result in death.

ALERT: Generator exhaust is toxic. If you lose power, ALWAYS put generators outside well away from doors, windows, and vents. Never use a generator inside homes, garages, crawlspaces, sheds, or similar areas. Carbon monoxide (CO) is deadly, can build up quickly, and linger for hours. More information.

PREVENTION IS THE BEST DEFENSE! Stay out of direct sun and wear sunscreen of SPF 15 or higher. Be extra careful about sensitive individuals like children, the elderly, or the sick. Never ever leave anyone or an animal alone in a car, or a pool or other risky location, not even for "just a few minutes."

Limit your outdoor activity to morning and evening. Spend time in cool places like a shopping mall, a library, or a theater.

Remember pets! Make sure all animals have plenty of fresh water and are able to move out of direct sunlight.

Also...

  • Save energy - reduce your home power use to help reduce brownouts or blackouts and smog/air pollution. Turn off nonessential lights, televisions, games, and computers, and unplug chargers.
  • Overexposure to the sun's ultraviolet (UV) radiation can result in a painful sunburn. It can also lead to more serious health problems, including skin cancer, premature aging of the skin, and other heatlh problems. Children are particularly at risk.
  • Learn more about Sun safety action steps.

Driving?

Drive smarter!  Find ways to help save fuel and reduce emissions if you're driving in hot weather.  

  • Roll the windows down at lower speeds; use the AC at highway speeds. Overcoming air drag at highways speeds uses more fuel than the air conditioner.
  • Drive with the windows open for a short time before using the AC, to let out the hot air before you run the AC.
  • Park in the shade or use a sunshade.
  • More about fuel economy in hot weather.

Don't top off!  When you fill up remember not to top off your gas tank. Topping off can spill gasoline which quickly evaporates into the air around you. Gasoline vapors can harm your family's health and make ozone pollution and smog worse. In hot weather, buy gas when it's cooler in the early morning or at night. 

Extreme heat can make drought worse. More about drought.

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