UL 1660 PDF

1 Scope

1.1 These requirements cover liquid-tight flexible nonmetallic conduit in the 3/8 – 4 (12 – 103) trade sizes of Type LFNC-A (Layered), Type LFNC-B (Integral), and Type LFNC-C (Corrugated) constructions. The conduit is intended for installation in accordance with the National Electrical Code (NEC), the CE Code, Part 1, and the Mexican Electrical Code, NOM-001-SEDE. The values in parentheses are metric trade designators of conduit.

1.2 Conduit covered by this Standard is intended for use in wet, dry, or oily locations at a maximum of 60°C (140°F), unless otherwise marked. (See Section 6.)

1.3 Fittings for liquid-tight flexible nonmetallic conduit are covered in UL 514B, CSA C22.2 No. 18.3, or NMX-J-017-ANCE.

Summary of Topics

This revision of ANSI/UL 1660 dated May 23, 2024 includes the addition of minimum inside diameter for trade sizes 2-1/2 and 3-1/2; Table 5