Changes to daylight-saving time

Throughout most of the U.S., daylight-saving time (DST) in 2007 will start at 2 a.m. on Sunday, March 11. The clocks are springing forward an hour three weeks earlier than usual because of a policy change mandated by the Energy Policy Act of 2005. Daylight time will also last one week longer in the fall, ending on Sunday, Nov. 4.  (For more information on the extended DST, see "Daylight saving time gets a new start.")

As annoying as it might be to arrive an hour late for a child's birthday party, golf tee time, or other activity because you forgot to reset your clocks, other problems caused by the extended daylight time could be far more harmful.

Unless you apply certain updates, your computer might be off by an hour for three weeks this spring, causing inaccuracy in other programs. Scheduled meetings, for example, might pop up at the wrong time, and transactions might receive incorrect time stamps.

Attempting to head off such issues, Microsoft and Apple are offering free patches to update computer systems as well as tips to ease confusion when you communicate with those whose computers haven't been updated.

Unfortunately, patches won't assuage all computer woes. You will need to manually update computers running a Windows operating system older than XP and Apple computers running an operating system before 10.3, even though they used to change to and from DST automatically. The same goes for some other electronics and appliances with clocks and/or calendars.

But there is a bright side to this change--you get an added hour of daylight for three weeks. The start of daylight time is also a great time to tackle household chores. When you're resetting your watches and clocks (don't forget the one in your car), use this annual event as a cue to do the tasks below. They'll enhance safety for you and your family year-round and save you some money on your utility bills, too.

Replace batteries in all smoke and carbon-monoxide alarms. Always use fresh batteries. And follow manufacturer's instructions to ensure that those essential devices are working properly. Also, replace any smoke alarm that's 10 or more years old and any CO alarm 5 or more years old with a new model. You'll find the manufacture date on the alarm. See our report on carbon-monoxide alarms and our exclusive interactive on smoke alarms for more information. (The CO-alarms report and Ratings are available to subscribers).

Reset clocks on appliances and electronics. Some newer appliances and electronics are equipped with a microchip that automatically resets clock displays at the beginning and end of daylight time. Check the owner's manual to determine which of yours do. You'll need to reset those that don't have a chip. To organize the process, make a list of all devices that you need to reset manually: clocks, TVs, DVD players/VCRs, fax machines, cameras, and thermostats. (It's especially important to reprogram your thermostat so that the heat in your home doesn't switch on earlier than you intend.) Reset everything on the list in one session so that no appliance or electronic device is forgotten.

Inspect vehicle lights. Inspect the entire lighting system in your car to ensure that all lights are working properly. Clean headlights and make sure they are correctly aligned according to the owner's manual.

Update your family disaster plan. To respond properly to a natural disaster or other cataclysmic event, you need to have a plan in place and the necessary supplies on hand, and be prepared to act.  See our free emergency guide to preparing for any storm or disaster.Plan accordingly when traveling. Some areas of the U.S. and some of its territories do not observe daylight time, including Hawaii, most of Arizona, American Samoa, Guam, Puerto Rico, and the Virgin Islands. And in Europe, daylight time runs from the last Sunday of March through the last Sunday of October.

Check storage areas for hazardous materials. Properly dispose of any materials that are outdated, no longer used, or in poor condition. Make sure those you keep are out of the reach of children or pets.

Program thermostats for savings. Shave up to 20 percent off your heating (and cooling) costs by lowering (and raising) your home thermostat 5° F at night and 10° F during the day if no one is home. Most electronic setback thermostats let you program different schedules for each day. Many automatically switch from heating to cooling, and some tell you when it's time to change your furnace or air-conditioner filters.

You can save on your utility bill by replacing the bulbs in just 25 percent of your most frequently used fixtures with compact fluorescent lightbulbs (CFLs). Some CFLs offer softer color and ballasts designed to eliminate humming. Also consider replacing torchère lamps that use halogen bulbs--they use 60 to 80 percent more energy than fixtures fitted with CFLs. Install motion or light sensors on outdoor lighting so that fixtures turn on only when needed.