43 12 00 Gas Compressors
43 12 37 Diaphragm Reciprocating Compressors
43 12 11Centrifugal Compressors43 12 13Diagonal or Mixed-flow Compressors43 12 16Axial-flow Compressors43 12 33Single-acting Reciprocating Compressors43 12 34Double-acting Reciprocating Compressors43 12 37Diaphragm Reciprocating Compressors43 12 51Rotary Screw Compressors43 12 53Rotary Vane Compressors43 12 56Rotary Liquid-ring Compressors43 12 57Rotary Scroll Compressors