Twice a year I make a quick blog post or tweet to watch out for nonstandard time conversions during the transition in and out of Daylight Saving Time. I figure it might be nice to get ahead of the curve this year as you may be starting to schedule your March webinars.
The key takeaway is that you should not make any assumptions about the equivalent starting time for people in other locations. It’s very easy to fall into the trap of common knowledge such as “London is five hours ahead of New York.” That is not always the case!
There is no global standards board for Daylight Saving Time (DST). Different countries can choose to observe it or not, and they can choose when it starts and ends. In many places, different localities within a country can choose their own DST conventions.
Here in the USA, Arizona, Hawaii, and Puerto Rico are examples of states and territories that do not change clocks for DST. In Canada, quite a few areas choose not to observe DST – and they don’t even correspond to the rest of the province they are located in!
In the USA and Canada, areas that observe DST will change their clocks on March 14 this year. In the UK and most of continental Europe, the time change won’t occur until March 28. In Palestine and Paraguay, clocks will change on March 27, while Australia and New Zealand will change their clocks on April 4 (except for those areas in Australia that choose not to observe DST).
So while you may think you know the time offset between two locations, you could be mistaken on any given date in late March and early April. This also applies to your audiences… Don’t trust them to figure out the starting time where they are based on your posted starting time where you are.
How do you deal with the situation? I usually prefer to list the local start time for a few representative major cities and then provide a clickable web link that lets people look up the equivalent time in other locations:
March 27, 2021 – 60 minutes – Free Admission
New York:9am / London:2pm / Dubai:5pm
Click here to find your local time
I prefer to use city names to avoid ambiguity. For instance, CST can mean US Central Standard Time or China Standard Time or Cuba Standard Time. IST is used for Indian Standard Time, Irish Standard Time, and Israel Standard Time. And in areas where time zones are nonstandard within a country or state, giving the city name makes it clear where to start the conversion.
The “click here” link I used in my example comes from a tremendously useful free online utility. Timeanddate.com provides an “Event Time Announcer” – you specify a date, time, and anchor location, and it generates a table showing equivalent times in other locations. You can include the generated page link to direct people to the custom timetable for your event. The website is very good about updating their algorithms to account for new legislation altering regional time calculations – It happens more frequently than you would guess.
The first time you use the tool, you may not notice options that let you customize the table even more to your liking. I put red highlights around some of the options that let you choose how the reference cities get listed. Pick the display you like and then just copy the resulting URL out of your browser address window.
This is a useful tool at any time of the year, for any online event. But it’s especially critical if you are scheduling something during the “shoulder season” of late March and early April when all bets are off as to what time it is from one city to the next.
* Fun fact for the fastidious… Time conversions are not always in 60-minute multiples. If your event starts on the hour in the USA, India and parts of Australia see it start on the half hour. And people in Nepal as well as a few small islands see it starting on the quarter hour!