The purpose of a Double Check Detector Fire Protection Backflow Prevention Assembly (herein referred to as the \u201cassembly\u201d) is to keep polluted water from fire protection systems from flowing into a potable water distribution system when some abnormality in the system causes the pressure to be temporarily higher in the polluted part of the system than in the potable water supply piping. These assemblies are also designed to detect low rates of flow up to 2.00 GPM (0.13 L\/s) caused by leakage or unauthorized use. This standard applies to Double Check Detector Assembly (DCDA) and Double Check Detector Assembly Type II (DCDA-II). The DCDA and DCDA-II assemblies consist of two (2) independently acting check valves, internally force loaded to a normally closed position. These assemblies are designed to operate under continuous pressure conditions. The assembly shall include two (2) properly located, tightly closing shut-off valves and properly located test cocks. The assemblies also include a bypass line which provides a visual or audible indication of system leakage or unauthorized use of water. This standard also applies to Manifold Double Check Detector Assemblies consisting of two (2) or more complete DCDA or DCDA-II assemblies in parallel.<\/p>\n
| PDF Pages<\/th>\n | PDF Title<\/th>\n<\/tr>\n | ||||||
|---|---|---|---|---|---|---|---|
| 11<\/td>\n | Section I 1.0 General 1.1 Application 1.2 Scope <\/td>\n<\/tr>\n | ||||||
| 12<\/td>\n | Table 1 1.3 Limitations on Design <\/td>\n<\/tr>\n | ||||||
| 14<\/td>\n | 1.4 Reference Standards <\/td>\n<\/tr>\n | ||||||
| 16<\/td>\n | Section II 2.0 Test Specimens 2.1 Samples Submitted for Test 2.2 Samples Tested 2.3 Drawings 2.4 Rejection 2.5 Manifold Assembly <\/td>\n<\/tr>\n | ||||||
| 17<\/td>\n | Section III 3.0 Performance Requirements and Compliance Testing 3.1 Independence of Components 3.2 Hydrostatic Test of Complete Assembly 3.3 Seat Leakage Test for Shut-off Valves <\/td>\n<\/tr>\n | ||||||
| 18<\/td>\n | 3.4 Hydrostatic Backpressure Test of Bypass Check (for DCDA-II Assemblies 3.5 Hydrostatic Backpressure Test of Checks <\/td>\n<\/tr>\n | ||||||
| 19<\/td>\n | 3.6 Allowable Pressure Loss at Rated Flow Figure 1 <\/td>\n<\/tr>\n | ||||||
| 20<\/td>\n | Figure 1A <\/td>\n<\/tr>\n | ||||||
| 21<\/td>\n | 3.7 Bypass Flow Detection 3.8 Drip Tightness of First Check <\/td>\n<\/tr>\n | ||||||
| 22<\/td>\n | 3.9 Drip Tightness of Second Check 3.10 Drip Tightness of Bypass Check (for DCDA-II Assemblies 3.11 Deterioration at Manufacturer\u2019s Extremes of Temperature and Pressure Ranges <\/td>\n<\/tr>\n | ||||||
| 23<\/td>\n | Table 2 <\/td>\n<\/tr>\n | ||||||
| 24<\/td>\n | 3.12 Cycle Test <\/td>\n<\/tr>\n | ||||||
| 25<\/td>\n | 3.13 Body Strength Test 3.14 Seat Adhesion Test 3.15 High Velocity Test <\/td>\n<\/tr>\n | ||||||
| 26<\/td>\n | 3.16 Field Evaluation Test for DCDA and DCDA-II Devices When Required by the \n Authority Having Jurisdiction <\/td>\n<\/tr>\n | ||||||
| 27<\/td>\n | Section IV 4.0 Detailed Requirements 4.1 Materials <\/td>\n<\/tr>\n | ||||||
| 28<\/td>\n | 4.2 Marking Instructions <\/td>\n<\/tr>\n | ||||||
| 29<\/td>\n | 4.3 Installation and Maintenance Instructions <\/td>\n<\/tr>\n | ||||||
| 30<\/td>\n | Section V 5.0 Definitions <\/td>\n<\/tr>\n | ||||||
| 31<\/td>\n | Appendix A – Installation Guidelines A1.0 Recommended Installation Guidelines A1.1 General A1.2 Orientation A1.3 Side Clearances <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" ASSE Standard #1048-2011 Performance Requirements for Double Check Detector Fire Protection Backflow Prevention Assemblies<\/b><\/p>\n |