Over the last twenty years or so, bridged conference calls have become so economical that few project managers are asked to account for the cost in their budgets. Consequently, as distributed projects run by “virtual” teams have proliferated, many of us spend a large part of our day on these calls, and it’s no longer uncommon to have people dialing in from different time zones, and even different continents. My personal record is six time zones on a conference call at the same time – U.S. Eastern, Central, Mountain, and Pacific, plus the respective time zones for Belarus and India. But any time a project manager has to integrate team members across time zones, it can be useful to understand time zone notation.
Coordinated Universal Time (UTC) is essentially Greenwich Mean Time, or the local time at the Royal Observatory near London. Folks who work in telecommunications or the military usually refer to it as Zulu time. All other time zones are expressed as “offsets” from UTC. For example, the U.S. Eastern time zone is UTC-5, read as “UTC minus 5.” Thus, when it is 2:00 PM in London, it is five hours earlier, or 9:00 AM in New York. Germany’s time zone is UTC+1, so local time in Frankfurt would be one hour later, or 3:00 PM. To get the difference between any two zones, just subtract the smaller number from the larger number. So the difference between Seattle (UTC-8) and Hong Kong (UTC+8) can be calculated as: 8 – (-8) = 16 hours.
When time zones were originally proposed, the basic idea was to have 24 zones, each about 15 degrees of longitude wide. However, a number of countries preferred to have one time zone for their entire population. In some cases, like Iran, Afghanistan, India and Venezuela, they created their own “zone” offset a half hour from the time zones to their east and west. India’s time zone is thus UTC+5:30. Canada’s province of Newfoundland even has their own zone (UTC-3:30), as do two of Australia’s states, Northern Territory and South Australia (UTC+9:30). Fortunately, a UTC map is available.
The other interesting wrinkle is daylight savings time (DST), also called “summer time” in the UK. At some point in the spring, clocks are “set forward” one hour, and in the fall, they are “set back” one hour, to standard time. If everyone did this at the same time, then there wouldn’t be a problem. However, while most of North America and Europe observe DST, most of South America, Asia and Africa do not; parts of Australia do, and parts do not; Hawaii, Arizona, Saskatchewan, and several smaller parts of Canada and Mexico do not. Fortunately, there is a world map available that depicts which areas use DST.
If your team and stakeholders are spread out enough to worry about time zones, add a column to your contacts list that includes the UTC and DST information. It’s a little thing, but it helps when planning your project communications schedule.