STAAD.Pro HelpDesignD. Design CodesD1.American CodesD1.K. American Codes - Steel Design per ANSI/AISC N690 Design CodesD1.L. American Codes - Steel Design per ASME NF Codes D1.L. American Codes - Steel Design per ASME NF Codes The following American Society of Mechanical Engineers – Nuclear Facility codes are available. D1.L.1. ASME NF 3000 - 1974 & 1977 CodesD1.L.2. ASME NF 3000 - 1989 CodeFor steel design, STAAD.Pro compares the actual stresses with the allowable stresses as defined by the American Society of Mechanical Engineers — Nuclear Facility (ASME NF) Code. The ASME NF-3000 1989 Code is used as the basis of this design.D1.L.3. ASME NF 3000 - 1998 CodeFor steel design, STAAD.Pro compares the actual stresses with the allowable stresses as defined by the American Society of Mechanical Engineers — Nuclear Facility (ASME NF) Code. The ASME NF-3000 1998 Code is used as the basis of this design.D1.L.4. ASME NF 3000 - 2001 & 2004 CodesD1.L.5. ASME NF 3000 Service Level ConditionsService Level Conditions are basically the loading conditions for which the plant structure and its components are to be designed. The same primary load can be multiplied by different factors to signify the different service levels. Also the load combinations for various service levels are different and pre-defined by the code.Parent Topic: D1.K. American Codes - Steel Design per ANSI/AISC N690 Design CodesParent Topic: D1.American Codes