IEC 60079-13:2010 gives requirements for the design, construction, assessment and testing and marking of rooms protected by pressurization in: - a room located in an explosive gas atmosphere or explosive dust atmosphere hazardous area that does not include an internal source of a flammable substance; - a room located in an explosive gas atmosphere or explosive dust atmosphere hazardous area that includes an internal source of a flammable substance; - a room located in a non-hazardous area that includes an internal source of a flammable substance. This publication is to be read in conjunction with IEC 60079-0:2007.