Definition(s)

Classified Locations

A classified location is a location classified as Division 1 or Division 2, or Zone 0, Zone 1, or Zone 2.

Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards

Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards

 

Class I location

A Class I location is one in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitable mixtures. (See NEC Article 500 and NEC Article 505 and API 500 and API 505.)

Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards

 

Class I, Division 1 location A

Class I, Division 1 location is a location: 1) in which ignitable concentrations of flammable gases or vapors exist continuously, intermittently, or periodically under normal operating conditions; or 2) in which ignitable concentration of such gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or 3) in which breakdown or faulty operation of equipment or processes might release ignitable concentrations of flammable gases or vapors, and might also cause simultaneous failure of electrical equipment (see NEC Article 500 and API 500).

Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards

 

Class I, Division 2 location

A Class I, Division 2 location is a location: 1) in which volatile flammable liquids or flammable gases are handled, processed, or used, but in which the hazardous liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only if accidental rupture or breakdown of such containers or systems or abnormal operation of equipment occurs; or 2) in which hazardous concentrations of gases or vapors are normally prevented by positive mechanical ventilation but that might become hazardous through failure or abnormal operation of the ventilating equipment; or 3) that is adjacent to a Class I, Division 1 location, and to which hazardous concentration of gases or vapors might occasionally be communicated unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided. (See NEC Article 500 and API 500.)

Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards

 

Classified locations

Classified locations are those in which flammable hydrocarbon gas or vapors, resulting from the drilling operations, may be present in quantities sufficient to produce an explosive or ignitable mixture. Location of these areas affect the design of the units’ machinery, electrical, and ventilation systems. (See Notes 1 and 2).

Notes:

  1. Further requirements with respect to hazardous locations are contained in part 111, subpart 111.105, of this chapter.
  2. For specific requirements for machinery and electrical installations on mobile offshore drilling units see Subchapters “F” and “J” of this chapter.

Source: Mobile Offshore Drilling Units, 46 CFR 107-109 (2013). Regulations

 

 

Comments are closed.