Year 2007 problem

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The Year 2007 problem also known as Y2K7 (or DST07) is an issue caused by a US-mandated change to daylight saving time, which has repercussions in the computer industry.^[1] Starting in 2007, daylight saving time in many jurisdictions of the United States and Canada begins earlier each spring (in fact, all the way back into winter) and runs later each fall than in previous years; in 2007, for instance, it started on the second Sunday in March and ended on the first Sunday in November.^[1]

Any device that automatically corrected its clock to match the time changes to daylight saving time, such as personal computers and VCRs, needed to be updated so that the device would know of the new rules.^[1] If the devices weren't updated, they showed an incorrect time for three weeks in March and one week in November, causing a number of problems, including having e-mail with wrong timestamps; events in calendaring software used on PDAs and other computers being displayed incorrectly, set for the wrong time, or syncing between devices that are aware of the changes in DST and those that aren't (e.g. between an updated BlackBerry or Palm device and a computer either of which required their own updates); and some authentication software, such as Kerberos in Mac OS, not behaving properly.^[1] To avoid these problems, users either have to update their devices manually when daylight saving time changes, or update their software to newer versions.

Contents 1 Countries affected 1.1 Areas changing in 2007[2] 2 Medical equipment 3 See also 4 References 5 External links

[edit] Countries affected

Implications of the changes in daylight saving time extended beyond the United States as neighbouring countries had to decide if they would change their DST rules to remain in step with the United States.

[edit] Areas changing in 2007^[2]

• United States (Not observed in Hawaii, American Samoa, Guam, Puerto Rico, the Virgin Islands and the state of Arizona [except the Navajo Nation, which observes daylight saving time due to its large size and location in three states.])^[3] Note especially that most of the state of Indiana did not observe daylight saving time until 2006, when most of the state adopted Eastern Time.^[4]

• Canada (except most of Saskatchewan, and a few isolated areas; also, Newfoundland switches at 00:01 rather than 02:00 local time)
• Cuba (switches at 00:00 local time)
• New Zealand extended daylight saving times starting in the last Sunday in September (instead of the first Sunday in October)

[edit] Medical equipment

Some medical devices and hospital equipment may generate adverse events because of the changes. These could harm patients and not be obvious to clinicians responsible for care. The FDA has published a preliminary public health notification on the subject.^[5]

[edit] See also

[edit] References

[edit] External links

• Extended Daylight Saving Time Review and Considerations A Review of the Potential Impact of Daylight Saving Time Changes in 2007 — A Reference for Users and Systems Administrators, Calendaring and Scheduling Consortium for 2007
• 2007 Time Zone Changes Will Impact Many Computers in Canada, the United States and Bermuda
• Are You Prepared for DST 2007? Considerations for 2007 changes
• Daylight Saving Time — The Year 2007 Problem January 11, 2007
• Change in Daylight Saving Time Effective 2007 by Mary Salvas on last edited 28 February 2007
• Techies Working To Stay Ahead Of Y2K7 Bug Daylight Saving Change Challenges Computer Programmers, KETV News.
• Daylight Saving Time May Bite the Out-of-Date by Andrew Laurence, 2007-01-29 (followup Daylight Saving Time Saved, by Andrew Laurence 2007-02-19)
• New 2007 Rules for Daylight Savings Time
• How to configure daylight saving time for the United States in 2007