Proposal to clarify the intent of the selected paragraphs to ensure that systems with with one service brake meet braking performance requirements using only that brake system (i.e, without any assistance from the secondary brake system). There had been an interpretation that for systems with two service brakes each brake had to meet the requirements which would result in higher stringency levels than intended by the requirement for single brake systems.
The proposal also clarifies the parts of the braking system that should be considered with respect to hydraulic brake and mechanical transmissions and further clarifies that the test procedures are designed to simulate a brake failure rather than produce one.
21. The expert from IMMA introduced on behalf of the sponsor, Italy, ECE/TRANS/WP.29/GRRF/2014/3 and ECE/TRANS/WP.29/GRRF/2014/4 as amended by GRRF-76-35-Rev.1, proposing similar amendments to those proposed for Regulation No. 78 (see para. 20, agenda item 5a). These proposals received comments and the expert from IMMA consolidated these requested changes into a revised proposal (GRRF-76-44). GRRF requested the secretariat to distribute GRRF-76-44 with an official symbol at its September 2014 session.