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OOSC, Part II, Item 1. Brake Systems, d. Trailer Breakaway and Emergency Braking

Entry DateAugust 14, 2009
Issue Number09-040-VEH
NameCharles Longfellow
AgencyTexas Department of Public Safety
AddressP.O. Box 4087Austin, TX, 78773United StatesMap It (opens in a new tab)
Phone512-424-2880
Fax(512) 424-5262
Email[email protected]
CommitteeVehicle Committee
StatusClosed
Summary of Issue

The April 1, 2009 North American Standard Out-of-Service Criteria (OOSC) states a trailer is out-of-service for a ?missing or inoperable breakaway braking system.? Trailer manufacturers commonly place two spring brakes on a single axle trailer and four on a tandem axle. The question arises, how many spring brakes must be caged or found inoperable to place the trailer out-of-service? Webster?s defines a ?system? as ?an assemblage or combination of things or parts forming a complex or unitary whole.? If a tandem axle has four spring brakes and one, two or three are caged, then has the system lost its complex or unitary whole? Or is one working spring brake out of four still considered sufficient to comply with the requirements of a breakaway braking system?

Justification or Need

To determine the applicability of the OOSC for missing or inoperable breakaway braking systems.

Request for Action

We would like a better definition of the application of the out-of-service language.