UL 122001

General Requirements for Electrical Ignition Systems for Internal Combustion Engines in Class I, Division 2 or Zone 2, Hazardous (Classified) Locations

This standard provides minimum construction and test requirements in addition to manufacturer installation and maintenance recommendations for the safe operation of ignition systems and components for spark-ignited reciprocating internal combustion engines in Class I, Division 2, Group C or D or Class I, Zone 2, Group IIB or IIA, hazardous (classified) locations. These requirements apply to systems rated for normal operation with secondary voltages less than or equal to 35 kV.

This standard is intended to cover only ignition systems of reciprocating internal combustion engines that are stationary when in operation. This does not include any application where the engine would be in motion (vehicles) while operating. Applications addressed by the scope of this document include but are not limited to gas compressors, electric power generators, and pumps.

This standard applies to ignition systems suitable for use in an ambient temperature range of -40°C to +70°C (-40°F to +158°F).


  • Edition Number: 1
  • Edition Date: 08/29/2014
  • Price Code: A
  • Type: ulisa
  • ANSI Approved: 08/29/2014
  • DOD Approved: