Accidents
Various studies show an increase in the rate of traffic accidents immediately after the switch to daylight saving time. This is mainly attributed to the relative sleep deprivation experienced by many people due to the "lost" hour, as well as the fact that more trips are made at dawn or in the dark. Although not all studies come to this conclusion, it seems very sensible to prepare well for the switch to Central European Summer Time (CEST) in spring (See Tips for Daylight Saving Time), or at least leave the car in the garage on the Monday after the switch.
Conversely, there is evidence to suggest that the transition to standard time (winter time), during which one gets an "extra" hour, actually reduces the risk of traffic accidents. And even daylight saving time itself - disregarding the time around the transition - probably has a positive effect, as the main traffic times generally occur during daylight hours.
- Study from the University of British Columbia on the correlation between daylight saving time and traffic accidents (New England Journal of Medicine, English)
- Study from the National Institute for Health and Welfare, Helsinki, on the same topic (English)
- Caution in Traffic: Daylight Saving Time Increases Risk of Wildlife Accidents (shz.de)
Impact of Daylight Saving Time on Timetables
Especially the trains have always been affected by time changes - even more so in the past, as local time measurement was still in use, meaning time shifts did not only occur twice a year, but on almost every journey between two cities.
To limit the resulting confusion, the railway introduced its own time zones - the Berlin, Munich, Stuttgart, Karlsruhe, or Ludwigshafen time, which the trains adhered to and which was additionally displayed at the stations besides local time. The standardization of times within Germany to Central European Time, which was demanded primarily by the railway companies and introduced in 1893, significantly simplified the situation.
The time changes resulting from daylight saving time are actually a piece of cake and are now handled very routine by Deutsche Bahn. The procedure is as follows:
- During the switch to daylight saving time, trains are missing the hour between 2 and 3 a.m. Freight trains are sent off early if possible to arrive on time. S-Bahn trains that would only be in service during the missing hour are simply canceled.
For night trains, any overnight stops are shortened to arrive at the destination without delay.
All others who do not have this option, simply arrive late. - During the switch to standard time (winter time), the hour between 2 and 3 a.m. is repeated, making the night longer.
During this night, night trains simply halt for an hour at a suitable station to avoid arriving too early.
S-Bahn trains that depart during the double hour depart "twice" that night, which naturally requires an increased number of vehicles and personnel.
These problems can also occur with air travel, but all airlines plan their flights according to Greenwich Mean Time, so that local time essentially does not matter and is only indicated on the passengers' travel documents. However, difficulties can still arise in individual cases, such as in 2015 when the Turkish government unexpectedly postponed the time change, causing the departure times of all flights from Turkey to be delayed by one hour.