Clause 3.2, Abbreviations: Added abbreviation for ASVB

Transcription

1 CSA B64.0, Definitions, general requirements and test methods for vacuum breakers and backflow preventers General: The changes to this standard are editorial in nature and do not have an impact on currently listed products. It is important to note that a new standard, CSA B Vacuum breaker, air space type (ASVB), was added to the series. Clause 3.1, Definitions: Added a definition for air space type vacuum breaker (ASVB) air gap, and added text to clarify the definition of reduced pressure principle (RP). Clause 3.2, Abbreviations: Added abbreviation for ASVB Clause 6.7.1, Test Apparatus: Updated the referenced standard as follows: Pressure gauges shall be located as specified in ANSI/ISA

2 C SA B Atmospheric vacuum breakers (AVB) General: The changes to this standard might have an impact on currently listed products. Clause 4.1, General: Changed the excepted clauses as follows: AVB devices shall comply with the requirements specified in this Standard and in CSA B64.0, with the exception of those specified in Clauses 5.3, 5.4, 5.5 and of CSA B64.0. The clauses from CSA B64.0 are as follows: Clause 5.3, Backflow under positive back pressure in backflow preventers with two check valves There shall be no backflow, as indicated by a drop in pressure, when backflow preventers with two check valves are tested in accordance with Clause 6.5. Clause 5.4, Check valve sealing pressure: Each check valve shall be drip tight, as indicated by no drop in pressure, when tested in accordance with Clause 6.6. Clause 5.5, Corrosion resistance: External chrome plated parts, when tested in accordance with Clause 6.8, shall exhibit not more than one corrosion spot on any 645 mm2 of surface, except that there may be three minor spots on each 25 mm length of parting line. Spots shall be not more than 0.8 mm in their major dimension. Clause 5.6, Deterioration in hot water: Backflow preventers and vacuum breakers intended for hot water applications shall be tested in accordance with Clause 6.9. There shall be no change in the physical characteristics of the materials that would prevent compliance with the requirements specified in this Standard and in the applicable product Standard in the CSA B64 Series. Clause 5.7, Life cycle test and field test for PVB and SRPVB devices and RP, RPF, DCVA, DCVAF, and SCVAF backflow preventers: General Devices covered by CSA B (PVB), B (SRPVB), B64.4 (RP), B (RPF), B64.5 (DCVA), B (DCVAF), and B64.9 (SCVAF) shall be tested in accordance with either Clause 6.10 or 6.11 of this Standard after successful completion of all other required tests Life cycle test When tested in accordance with Clause 6.10, there shall be no permanent deformation of parts or other change that would adversely affect the functioning of the backflow preventer or vacuum breaker.

3 5.7.3 Twelve month field test When tested in accordance with Clause 6.11, each backflow preventer or vacuum breaker shall give trouble free service for a minimum period of 12 consecutive months. There shall be no permanent deformation of parts or other change that would adversely affect the functioning of the backflow preventer or vacuum breaker.

4 C SA B Pressure vacuum breakers (PVB) General: There were no changes to the standard.

5 C SA B64.2, Hose connection vacuum breakers (HCVB) General: There changes to this standard are editorial in nature and do not have an impact on currently listed products. Clause 6.2, Test for leakage from the atmospheric vent: Editorially changed as follows; (a) Install the specimen in the test set up illustrated in Figure 2 of this Standard.

6 C SA B , Hose connection dual check vacuum breakers (HCDVB) General: The changes to this standard are editorial in nature and do not have an impact on currently listed products. Clause 6.2, Back siphonage and back pressure: Editorially changed as follows: (g) For HCDVB devices intended for use in other than cold water, the tests in Items (c) to (f) shall be repeated with water at the maximum rated temperature. Clause 6.4, Non removable feature: Clause 6.4.2: Editorially changed as follows: HCDVB devices that cannot be removed by this the method specified in Clause shall be considered non removable. Figure 1, Set up for backflow through outlet check valve test for HCDVB devices: Editorially revised the referenced clauses as follows: (See Clauses 6.1(a) and (b) and 6.2(a) and (b).)

7 C SA B64.4, Reduced pressure principle (RP) backflow preventers General: The changes to this standard are editorial in nature and do not have an impact on currently listed products. Table 3, Relief port minimum flow rate: Editorially corrected the referenced clauses as follows: (See Clauses , , , and of this Standard and Clauses and of CSA B64.0.)

8 C SA B64.6 Dual check valve (DuC) backflow preventers General: There were no changes to the standard.