scope:

This Standard covers the selection, installation, maintenance, and field testing of backflow prevention devices. Additional information on how backflow due to back siphonage and back pressure occurs and on the selection and application of specific devices is included in Appendices A, B, and C.

This Standard does not include requirements for materials, construction, and performance tests of the backflow preventer. Such requirements for the majority of the devices are covered in the CAN/CSA-B64 Series and CSA Standard B125 (see Table 1).

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 the Standard. Notes to figures and tables are to be considered part of the figure or table and are written as mandatory requirements. Legends to figures are to be considered mandatory requirements.

This Standard is predominantly written in SI (metric) units; for conversion tables, see Appendix D. However, because the test equipment currently available was designed in yard-pound units, calibration must be in those same units and therefore the requirements in the relevant Clauses (6.4.2.1, 6.5.1, 6.6.1, and 6.7.1) are also specified in yard-pound units