UL STANDARD FOR SAFETY Explosive Atmospheres – Part 13: Equipment Protection by Pressurized Room "p" and Artificially Ventilated Room "v"
|Publication Date:||20 April 2020|
1DV.1 DR Modification of the Clause 1 to replace with the following:
1DV.1.1 This standard gives requirements for the design, construction, assessment, verification and marking of rooms used to protect internal equipment:
- located in a Zone 1 or Zone 2 or Zone 21 or Zone 22 explosive atmosphere (an area normally requiring an equipment protection level (EPL) Gb, Gc, Db or Dc) without an internal source of gas/vapour release and protected by pressurization;
- located in a Zone 2 explosive atmosphere (an area normally requiring EPL Gc) with or without an internal source of gas/vapour release and protected by artificial ventilation;
- located in a non-hazardous area, containing an internal source of gas/vapour release and protected by artificial ventilation;
- located in a Zone 1 or Zone 2 or Zone 21 or Zone 22 explosive atmosphere (an area normally requiring EPL Gb, Gc, Db or Dc), containing an internal source of gas/vapour release and protected by both pressurization and artificial ventilation.
1DV.1.2 DE The term "room" used in this document includes single rooms, multiple rooms, a complete building or a room contained within a building. A room is intended to facilitate the entry of personnel. The term "room" also includes inlet and outlet ducts. An acoustic hood and other like enclosures designed to permit the entry of personnel can be considered as a room.
This document also includes requirements related safety devices and controls necessary to ensure that artificial ventilation, purging and pressurization is established and maintained.
A room assembled or constructed on site, can be either on land or off-shore. The room is primarily intended for installation by an end-user but could be constructed and assessed at a manufacturer's facility, where the final construction such as ducting can be completed on site.
Rooms can be located in an explosive gas atmosphere requiring EPL Gb or Gc, or a combustible dust atmosphere requiring EPL Db, or Dc.
This document does not specify the methods that may be required to ensure adequate air quality for personnel with regard to toxicity and temperature within the room. National or other regulations and requirements may exist to ensure the safety of personnel in this regard.
Protection of rooms by using an inert gas or a flammable gas is outside of the scope of this document. It is recognized that such applications are special cases, which in part may be addressed using the principles from UL 60079-2, but in all probability will also be the subject of additional, stringent engineering standards, procedures and practices, Pressurized enclosures for equipment that are not intended to facilitate the entry of personnel are addressed in UL 60079-2, and are not in the scope of this document.
1DV.1.3 DR NOTE Maintenance recommendations are contained in Annex A
This document supplements and modifies the general requirements of UL 60079-0, except exclusions as indicated in Table 1DV.1. Where a requirement of this document conflicts with a requirement of UL 60079-0, the requirement of this document takes precedence.
1DV.1.4 DR Where references are made to IEC, IEC/IEEE, ISO, and ISO/IEC standards, the referenced requirements found in these standards shall apply as modified by any applicable U.S. National Differences for the standard (see Clause 2).