CSN EN 14222 This document specifies requirements for electrically heated steam boilers manufactured from stainless steel specifically dedicated for generating steam for sterilizers and disinfectors. This document covers only steam boilers that are heated by immersion heaters and which have a maximum allowable pressure (PS) of not greater than 6 bar, a maximum volume (V) of 1 000 litres and a product of PS . V not greater than 3 000 bar . l. Original English text of CSN EN Standard. The price of the Standard included all amendments and correcturs.