Type Designation 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
NFPA 505 Fire Safety Standard for Powered Industrial Trucks Including Type Designations, Areas of Use, Conversions, Maintenance, and Operations, 2002 ed. (Std: Fr Sfty for Powered Ind Trucks Incl Type Designations, Areas of Use, Covr, Maint and Opr - Amer) {328 NFC}