I.S. EN 13959:2004

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
   3.1 Anti-pollution check valves
   3.2 Flanged anti-pollution check valves; class a and
         class b
   3.3 Combined product
4 Nominal size
5 Designation
6 Marking and technical documents
   6.1 Marking
   6.2 Technical documents
7 Symbolization
8 General design characteristics
   8.1 Overall length and diameters of check valves
   8.2 End connections
   8.3 Test and drain ports
   8.4 Other characteristics
9 Physio-chemical characteristics
   9.1 Materials
   9.2 Nature of mater
10 Test Arrangements
   10.1 Sequence of testing
   10.2 Apparatus
11 Hydraulic and mechanical characteristics
   11.1 High velocity (stage 1)
   11.2 Flow rate/pressure loss (stage 2)
   11.3 Mechanical strength of the body (stage 3)
   11.4 Bending moment (stage 4)
   11.5 Pressure tightness under a low reverse pressure
         differential (stage 5)
   11.6 Pressure tightness under a high reverse pressure
         and verification that the check valve has not
         jammed (stage 6)
   11.7 Pressure differential at which the check valve
         closes (stage 7)
   11.8 Compatibility with products used for disinfection
         of networks (stage 8)
   11.9 Endurance (stage 9)
   11.10 Pressure tightness under a low reverse pressure
         differential (stage 10)
   11.11 Pressure tightness under a high reverse pressure
         and verification that the check valve has not
         jammed (stage 11)
   11.12 Pressure differential at which the check valve
         closes (stage 12)
12 General working characteristics
   12.1 Resistance to corrosion
   12.2 Acoustic characteristics
13 Presentation at delivery
Annex A (informative) Numbers of test devices/tests

Describes: - field of application of anti-pollution check valves; - backflow prevention properties, dimensional and physio-chemical properties, and properties of general hydraulic, mechanical and acoustic design for anti-pollution check valves of nominal sizes DN 6 to DN 250 inclusive; - family E, type A, controllable anti-pollution check valve (with test port); - family E, type B, non-controllable anti-pollution check valve, including cartridge check valve; - family E, type C, controllable anti-pollution double check valve (with test ports); - family E, type D, non-controllable anti-pollution double check valve, including cartridge double check valve; - test procedures and requirements for verifying the backflow protection properties of stop valves, draw-off taps etc. which incorporate a check valve function. Stop valves, draw off taps etc, need also to comply with a recognised standard; - marking; - presentation at delivery.