today I was looking through the EPW - weatherfiles on http://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data.cfm . According to the pdf-file explaining the EPW weather data definition in the headers there should be something to find about the daylights savings periods. But in every file I looked into I could only find the following line:"HOLIDAYS/DAYLIGHT SAVINGS,No,0,0,0".