This recommended practice covers minimum requirements for air brake hose assemblies made from reinforced elastomeric hose and suitable fittings for use in automotive air brake systems including flexible connections from frame to axle, tractor to trailer, trailer to trailer and other unshielded air lines with air pressures up to 1 MPa, that are exposed to potential pull or impact. This hose is not to be used where temperatures, external or internal, fall outside the range of -40 °C to +100 °C.
The standard currently only provides for use of reattachable fittings for sizes 3/8, 7/16, and 1/2SP on type A hoses. An end user has an application for reattachable fittings for the 1/4 size. Therefore there is a need in the industry to add the 1/4 size to section 4.2 for type A hose.