Abstract： ASME A112.18.3:2002 pdf download.PERFORMANCE REQUIREMENTSFOR BACKFLOW PROTECTIONDFVICES AND SYSTEMS INPLUMBING FIXTURE FITTINCS. 7.3 Conformance Any physical damage to internal devices known to preclude functional performance shall be cause...

ASME A112.18.3:2002 pdf download.PERFORMANCE REQUIREMENTSFOR BACKFLOW PROTECTIONDFVICES AND SYSTEMS INPLUMBING FIXTURE FITTINCS.

7.3 Conformance

Any physical damage to internal devices known to preclude functional performance shall be cause for reqection

allowable failures shall not exceed the values shown in Table 1

8 FIXTURE FITTiNGS WITH INTERNAL DEVICES COMPLYING WITH PARAS. 6 AND 7

The purpose of this paragraph is to define the requiremt-nts and test procedures for the evaluation of finished

products incorporating certified backflow protection devices which have been demonstrated to be in compliance with paras. 6 and 7 of this Standard.

8.1 Health and Safety

8.1.1 There shall be at least two hackilow prevention devices, in series proven by tests as in compliance with

para. 7 of this Standard. They shall operate independently as integral parts of the fixture fitting. At least one device shall be a check valve, called the primary check in this Standard.

Among the protection devices are

(a) check valves

(b) vents to air

(c) vacuum breakers

(d) automatic diverters

8.1.2 Contaminants shall not enter the potable water system through backf low nor shall contaminants be allowed to enter the fitting beyond the first barrier when the backflosv preventer is operating properly. The test shall be

in accordance with para. 12.

8.1.3 The manufacturer shall specify the type and location of the hackuiow protection system in the product

literature or in the installation instructions.

8.2 Performance Tests

8.2.1 Selection of Test Specimens. To comply with this Standard, two specinsens will be selected at random from a lot of five production fittings.

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