Preface 

This is the second edition of CSA M424.3, Braking performance - Rubber-tired, self-propelled underground mining machines . It supersedes the previous edition published in 1990. Changes to this edition include: a) maximum rated speed and rated gross mass limitation have been removed; b) service braking requirements have been added for hydrostatic drive systems, systems with combined brake and steering function, and machines designed to tow trailers; c) requirement for test report has been added; d) a new Annex on maximum force levels for braking system controls during performance tests; and e) a new Annex with calculated values for stopping distances. CSA group acknowledges that the development of this Standard was made possible, in part, by the financial support of CanmetMINING, Lands and Minerals Sector, Department of Natural Resources Canada. This Standard was developed by CSA Group with funding support provided by the Canadian Association of Administrators of Labour Law - Occupational Safety and Health (CAALL-OSH), including provincial and territorial governments, as well as the Government of Canada. CSA Group is solely responsible for the content of this Standard, and CSA Group and the funding bodies disclaim any liability in connection with the use of the information contained herein. This Standard has been developed in compliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group. 

Scope 

1.1 General This Standard describes minimum performance criteria for the service braking system, secondary braking system, and parking system for rubber-tired, self-propelled underground mining machines. This Standard provides minimum braking system performance for rubber-tired, self-propelled underground machines, and test criteria by which machine braking system performance may be verified. 

Notes: 1) Additional requirements for brake systems on machines used in coal and gassy underground mines are found in CSA M424.1. 2) Additional requirements for dynamic and continuous retarding systems are found in CSA M424.4. 

1.2 Terminology In this Standard, "shall" is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; "should" is used to express a recommendation or that which is advised but not required; and "may" is used to express an option or that which is permissible within the limits of the Standard. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (nonmandatory) to define their application.