UL Standard for Safety Requirements for Process Sealing Between Electrical Systems and Flammable or Combustible Process Fluids
|Publication Date:||12 May 2017|
This document provides specific requirements for process sealing between electrical systems and flammable or combustible process fluids where a failure could allow the migration of process fluids directly into the electrical system.
NOTE 1: Some definitions differentiate the terms "flammable" and "combustible" liquids on the basis of their flashpoints. Combustible liquids under conditions of elevated pressure and/or temperature can lead to the formation of flammable mists and aerosols which are within the scope of this standard.
This document contains requirements for construction and testing of single seal equipment, dual seal equipment, and add-on secondary seals.
The requirements of this document apply to process seals as described in the process sealing sections of NFPA 70 in the United States or CSA C22.1 in Canada but does not address the additional requirements for electrical conduit and cable seals as addressed in UL 1203 (CSA C22.2 No. 30) and UL 2225 (CSA C22.2 No. 174). Requirements for basic electrical safety and explosion protection are not addressed by this document, but may apply to equipment under investigation. The secondary effects of leakage to the environment are not addressed by this standard.