This is the fourth edition of CSA B149.3, Code for the field approval of fuel-related components on appliances and equipment. It supersedes the previous editions, published in 2005 and 2000 by the Canadian Standards Association (CSA) as CAN/CSA-B149.3, and in 1989 by the Canadian Gas Association (CGA) as CAN/CGA-B149.3.
This Code contains the requirements for fuel-related components and accessories and their assembly on an appliance utilizing gas, downstream of the manual shut-off valve specified in Clause 6.18.2 of CSA B149.1. Clause 13 of this Code contains additional requirements for process ovens, including bakery ovens, process furnaces, and atmosphere generators operating at approximately atmospheric pressure and used by industry for the processing of materials.
This Code does not apply to
(a) installations in marine pipeline terminals;
(b) gas where used as a feedstock in petroleum refineries or chemical plants;
(c) gas designated for storage or handling, or both, at liquefied petroleum gas bulk plants;
(d) gas where used for natural gas for vehicles;
(e) a new appliance for which there is an approved Standard;
(f) a manually operated appliance with an input not exceeding 20 000 Btuh (6 kW) used for industrial applications; and
(g) other fuels used in combination with gas.
When another fuel is used in the installation and in combination with gas, the safe operation of that fuel should be acceptable to the authority having jurisdiction.
Requirements contained herein apply only to that portion of an appliance using gas as defined in Clause 1.7, atmosphere gas, and reaction gas.
The requirements contained in this Code apply
(a) to new non-certified appliances and equipment of all inputs for which there is no approved Standard;
(b) when the upgrading of an existing certified or non-certified appliance is required; and
(c) to programmable logic controllers or microprocessor-based controls used for flame safety.
The requirements contained in this Code may be used to replace or supplement an approved Standard with the permission of the authority having jurisdiction.
When the term gas is used, the requirements of this Code include, and apply equally to, any of the following gases or mixtures of them: natural gas, manufactured gas, propane, propane air, propylene, butane (normal butane or isobutane), and butylene.
The values given in yard/pound units are the standard. The values given in parentheses are for information only.
In this Code, unless approved otherwise by the authority having jurisdiction, shall indicates a mandatory requirement; should indicates a recommendation or that which is advised but not mandatory; and may indicates an advisory or optional statement. Notes to the text do not include mandatory or alternative requirements. The purpose of a note is to separate from the text explanatory or informative material that is not properly a part of this Code. Notes to figures and tables, however, are considered part of the figure or table and may be written as mandatory requirements. Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.