UL Standard for Safety Requirements for Process Sealing Between Electrical Systems and Flammable or Combustible Process Fluids (Second Edition; Reprint with revisions through and including June 6@ 2016)
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. 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 ANSI/NFPA 70 in the United States or CSA C22.1 in Canada and not to electrical conduit and cable seals. 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 document.