UL 558 PDF

1 Scope

1.1 These requirements cover the fire safety aspects of industrial trucks with internal-combustion engines, such as tractors, platform-lift trucks, fork-lift trucks, and other specialized vehicles for industrial use. These requirements do not cover other possible safety aspects of such equipment.

1.2 These requirements do not cover farm or road vehicles or automotive vehicles for highway use.

1.3 The Fire Safety Standard for Powered Industrial Trucks Including Type Designations, Areas of Use, Conversions, Maintenance, and Operations, NFPA 505, identifies internal combustion engine powered industrial trucks as follows:

1. Types G, D, LP, CN, G/CN, and G/LP – A unit powered by gasoline (G), diesel (D), LP-gas (LP), compressed natural gas (CN), either gasoline or compressed natural gas (G/CN), or either gasoline or liquefied petroleum gas (G/LP), that has minimum acceptable safeguards against inherent fire hazards.

2. Types GS, DS, LPS, CNS, GS/CNS, and GS/LPS – A unit powered by gasoline (GS), diesel (DS), LP-gas (LPS), compressed natural gas (CNS), either gasoline or compressed natural gas (GS/CNS), or either gasoline or liquefied petroleum gas (GS/LPS) that, in addition to meeting all the requirements for Types G, D, LP, CN, G/CN, and G/LP, is provided with additional safeguards to the exhaust, fuel and electric systems.

3. Type DY – A diesel-powered unit that has all the safeguards of Type DS units and, in addition, any electric equipment is completely enclosed and equipped with temperature limitation features.

Summary of Topics

This new Eleventh edition of ANSI/CAN/UL 558 dated May 22, 2025 incorporates editorial changes including renumbering and reformatting to align with current style; as well as an adoption for a joint UL Standard for the United States and Canada.