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Cool Yourself and Your Home Safely This Summer

Summer, 2005 - For many people, the heat of summer is more than uncomfortable, it's downright dangerous.

The Centers for Disease Control and Prevention (CDC) says that excessive heat exposure killed 8,015 people in the United States from 1979 to 1999. During this 20-year period, more people died from extreme heat than from hurricanes, lightning, tornadoes, floods, and earthquakes combined. And heat is an international threat, killing more than 11,000 people in France in August 2003.

As summer begins, the safety experts at Underwriters Laboratories Inc. (UL), the not-for-profit product safety testing organization, offer advice on avoiding heat injuries by keeping your home cool.

The common recommendations for avoiding heat injuries include frequently drinking water and other non-alcoholic fluids and avoiding strenuous activities during the heat of the day. However, the CDC safety cites air-conditioning as the No.1 protection against heat-related illness and death.

"Air conditioning can help protect you and your family against summer heat and heat-related illnesses," says John Drengenberg, manager of Consumer Affairs for UL. "And, if you can't or don't want to air condition the whole house, window or room air conditioners can be a cost-efficient and effective method to beat the heat."

When you're selecting a room air conditioner, bigger isn't always better. An air conditioner that's too small won't be able to cool a large room, but an air conditioner that's too large for the room will turn on and off too frequently.

Energy experts say that a 10-by-12-foot room will require an air conditioner with a cooling capacity of 5,000 British thermal units (Btu) per hour. A 20-by-20-foot room will take a 10,000 Btu air conditioner and if you're cooling a small home of about 1,200 square feet, you'll need a 23,000 Btu air conditioner.

Also, when you're buying a room air conditioner, look for the Energy Efficiency Ratio (EER) on the yellow Energy Guide label. The EER ranges from 8 to 12 with the higher EER numbers indicating higher efficiency.

Before you install a window air conditioner, ensure the electrical circuit and the outlet will handle the load. "Sometimes, window air conditioners are used in older residences and buildings that may not have the wiring capacity necessary to operate these units safely," Drengenberg says. "A licensed electrician can inspect your home's wiring and advise you whether it will safely handle air conditioning units."

Smaller room units work with a standard 115-volt outlet, while a larger 115-volt unit may need a separate electrical circuit. The biggest window units will require a 230/208-volt circuit. Never file or cut the plug blades or grounding pin to plug an appliance cord into an outlet. If an extension cord plug doesn't fit an outlet, have a qualified electrician replace the outlet.

UL safety experts advise positioning a window air conditioner so its cord will reach a wall outlet. However, if you must use an extension cord, follow this advice from UL:

  • Ensure you have the right cord for an air conditioner. "They're a special breed in the hardware store," Drengenberg says. These extension cords are three-pronged grounded cords and are often flat.
  • Inspect extension cords before you use them. Do not use extension cords that are cut or damaged.
  • Look for the UL Mark on the extension cord, which means that representative samples of the cord have been tested for safety hazards.
  • Ensure the plug's blades and grounding pin are present.
  • Don't run the cord under a carpet.

Other home cooling tips include:

  • Have your air conditioner cleaned and inspected before summer.
  • Conduct routine maintenance checks during the summer such as regularly changing or cleaning filters.
  • Set your air conditioner's thermostat at 78 degrees or higher.
  • Don't let heat build up and then attempt to cool areas immediately by turning the controls to maximum settings. Start units early and cool areas throughout the day.
  • Close blinds and curtains on the west and south sides of your home to block out the sun.
  • Turn off all unnecessary lights.
  • Prepare meals in a microwave instead of on a stove or oven.
  • Wait until late evening to use heat-producing appliances like ovens, dishwashers and clothes dryers.
  • Close off unused rooms.
  • Make sure your attic is properly ventilated.

Drengenberg also says to consider using floor or ceiling fans with your air conditioner to spread the cooled air more effectively through the room or your home. However, cooling experts note that fans cool people, not rooms. Fans don't cool air. Instead fans circulate air, making you feel cooler by evaporating your perspiration.

When you're selecting fans and air conditioners, look for the UL Mark. This mark indicates that representative samples of the appliance have been tested for safety hazards. If you're installing a ceiling fan, follow the manufacturer's instructions. Usually that means hanging the fan so that the blades are at least 7 feet above the floor, 2 feet from the wall and 1 foot below the ceiling. The instructions may also include ensuring the electrical outlet box has the UL Mark and is labeled for use with ceiling fans.

Whole-house or attic fans may also help cool your home by pulling cool air through the house and exhausting warm air through the attic. These fans are effective when operated at night and when the outside air is cooler than the inside. Window fans can boost ventilation, too, circulating cooler air from the outside and helping exhaust warmer air.

Finally, Drengenberg notes, if your home is not air-conditioned, you can cool off by going to malls, public libraries and other public facilities that are air-conditioned including heat-relief shelters.

For more tips on summer safety, visit the UL Web site at www.ul.com/consumers.

About Underwriters Laboratories

Underwriters Laboratories Inc. (UL) is an independent, not-for-profit product safety certification organization that has been testing products for more than 110 years. UL tests more than 19,000 types of products annually, and more than 19 billion UL Marks appear on products each year. Worldwide, the UL family of companies and its network of service providers include 58 laboratories, and testing and certification facilities.

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