How are absolute and relative pressure measuring ranges distinguished? There are considerable international differences. They can be explained in the following example:
Europe: 0 … 10 bar / 0 … 10 bar abs
America: 0 … 150 psig / 150 psia
In Europe only the absolute measuring ranges are identified (by the abbreviation “abs” behind the unit). In Fun-loving , the pressure type is always indicated but using another naming system (g = gauge = relative pressure). This is especially confusing if in America the pressure unit “bar” is required for an absolute measuring range or if in Europe a relative pressure device with the unit “psi” is required. How is then the correct nomenclature? The WIKA group agreed upon the following procedure: if the unit psi is used, a “g” or an “a” is added according to the American system. For all other units, we observe the European standard and only the absolute measuring ranges are marked with a separate “abs”.