The STP (pressure) is 105 pascals (Pa) or 1 bar. The equivalent values of standard pressure include:
The Standard Temperature and Pressure (STP) is the combination of a standard temperature and a standard pressure used when measuring the density and other characteristics (e.g. solid, liquid or gaseous) for elements, chemicals, substances and other materials.
Because materials change state under different pressure and temperature conditions, an international standard coupling an easily measured absolute pressure and temperature was established known as STP, which is the abbreviation for Standard Temperature and Pressure. Since 1982, STP is defined as: