This International Standard defines a range of climatological data required for building design, gives guidance on methods of measurement and proposes symbols to designate them. It does not deal with suffixes or concepts combining several types of data, or values derived from basic data such as degree-days or characteristic wind speed. The definitions and symbols given in this International Standard aim to harmonize the expression of climatological data which may be drawn on when drafting regulatory and standard documents and when definitions and symbols are required for building design and construction.