This European Standard is the product standard for insulating glass units, which defines insulating glass units, and ensures by means of the evaluation of conformity to this standard that over time: - energy savings are made because the U-value and solar factor do not change significantly; - health is preserved because sound reduction and vision do not change significantly; - safety is provided because mechanical resistance does not change significantly. It covers characteristics that are of importance for trade. Marking conditions are included. The main intended uses of the insulating glass units are installations in windows, doors, curtain walling, roofs