UL 60079-13-2020 pdf free download

UL 60079-13-2020 pdf free download.Explosive Atmospheres — Part 13: Equipment Protection by Pressurized Room “p” and Artificially Ventilated Room “v”.
Unless otherwise identified in Clauses 6 or 7, the requirements of Clause 5 apply to both types of protection (by pressurizahon and by artificial ventilation).
5.2 Source of clean air
5.2DV DE Modification of Clause 5.2 to replace with the following:
The source of clean air shall be determined from the nature of the process and the physical layout and should be from a non-hazardous area. Under certain conditions as prescribed below and in 62 and in Lj2, the source may be from a Zone 2 area.
When the air intake is from a Zone 2 area, in addition to the pressurization or ventilation system requirements, the following apply:
a) there shall be at least one flammable gas detector with alarm in the air intake itable for use in turbulent airflow and in duct application: and
b) there shall be at least one flammable gas detector with alarm within the room: and
C) flammable gas detection in the air intake shall be arranged to shut down the intake of air containing flammable vapour or gas Into the room on detection of 25 % of the limiting value; and
d) flammable gas detection and all other electrical equipment used for alarming and emergency actions/interlocks and the supply fan and motor shall have an EPL suitable for the area without pressurization or ventilation system.
Any clean air duct in a hazardous area shall throughout its length operate above atmospheric pressure in order to preclude the entry of any flammable or combustible material. Alternatively, a fan may be installed at the entrance to a room (thus operating the duct below atmospheric pressure) provided that the conditions above in j are met.
NOTE This allows for reasonable assurance that the internal atmosphere of the room is clean at all times, either by operating the duct at a positive pressure or by cpe. ting the duct at atrnosphe. ic pressure and monitoring the atmosphere of the room with a gas detector.
5.3 Environmental and air temperature conditions
The appropriate environmental and air temperature conditions for design as determined for the pressurization or ventilation system shall be documented.UL 60079-13-2020 pdf free download.