Purpose And Scope

This Recommended Practice (RP) covers the minimum requirements for fleet maintenance of air brake connections utilizing fractional-inch, non-metallic tubing. It is applicable to vehicles manufactured to U.S. domestic standards for fleet maintenance of air brake connections for both compression and push-connect DOT fittings.

The materials and products used for these air brake connections conform to fur SAE standards: SAE J844, J246, J1131, and J2494-3, and U.S. Department of Tranportation (DOT) Federal Motor Vehicle Safety Standard (FMVSS) No. 106, Brake Hoses.  This RP includes requirements for the following areas:

1. Non-metallic (nylon reinforced) tubing as manufactured for use in air brake systems. (SAE J844)
2. General and dimensional specification for tube fittings designed for assembling to SAE (nylon) tubing. (SAE J246)
3. Performance requirements for air brake piping which established minimum qualifications for tensile and pressure capabilities, vibrational durability under cyclic temperatures, serviceability, and fitting compatibility. (SAE J1131)
4. Identification following SAE J844 (nylon) tubing and SAE J246 tube fittings, which shall be marked in accordance with applicable SAE and DOT, NHTSA Standard 106 Marking Requirements, in such a manner as to prevent mixing of inch and metric tubing, which is not included at this time.
5. DOT Push-connect air fittings for pneumatic applications. Tubing requirement, suggested protocol for tube preparation, assembly/disassembly. (SAE J2494-3)