1、ASSE Standard #1048-2011ASSE Board Approved: August 2011 ANSI Approved: August 2011 An American National StandardPerformance Requirements for Double Check Detector Fire Protection Backflow Prevention AssembliesASSE InternationalDouble Check Detector Fire Protection Backflow Prevention Assemblies iAS
2、SE 1048-2011General InformationNeither this standard, nor any portion thereof, may be reproduced without the written consent of the ASSE International.Instructions for receiving authorization to display the ASSE Seal are available from ASSEs International Office. Organizations wishing to adopt or li
3、st any ASSE Standard should print the ASSE Standard number on the cover page first and in equal or larger type to that of the adopting or listing organization.ASSE InternationalMokena, IllinoisCopyright 2011, 2009, 2005, 1999, 1993, 1990All rights reserved.ii Double Check Detector Fire Protection Ba
4、ckflow Prevention AssembliesASSE 1048-2011Double Check Detector Fire Protection Backflow Prevention Assemblies iiiASSE 1048-2011ForewordThis foreword shall not be considered a part of the standard. However, it is offered to provide background information.ASSE Product Standards are developed in the i
5、nterest of consumer safety.The recognition of probable sources or causes of contamination of a potable water supply system and the application of essential devices, or means, to prevent the entrance of contaminants to the potable water system, causing it to become unfit for human consumption, is vit
6、al to the maintenance of its continued potability.This standard focuses on those devices, known as Double Check Detector Fire Protection Backflow Prevention Assemblies (RPDF), which will fulfill this protective need. This standard was retitled during the 1999 revision to add “fire protection” to bet
7、ter describe the devices primary use.Typically installed but not limited to fire protection systems, the devices described are primarily designed for two functions. The protection of the public water supply from contaminants found in fire sprinkler systems is a primary function for a backflow preven
8、ter. These assemblies are also designed to detect low rates of flow up to 2.00 GPM (0.13 L/s) within the sprinkler system caused by leakage or unauthorized use. This standard also allows provisions for alarm signaling devices to be included in the assembly.Although many of the material specification
9、s are detailed within Section 4.1 of this standard, it is the responsibility of the manufacturer and installer to comply with the relevant jurisdictional requirements. The working group, which developed this standard revision, was set up within the framework of the Product Standards Committee of ASS
10、E International.Recognition is made of the time volunteered by members of this working group and of the support of the manufacturers who participated in meetings for this standard.This standard does not imply ASSEs endorsement of a product which conforms to these requirements.Compliance with this st
11、andard does not imply acceptance by any code body.It is recommended that these devices be installed consistent with local codes by qualified and trained professionals.iv Double Check Detector Fire Protection Backflow Prevention AssembliesASSE 1048-2011This standard was promulgated in accordance with
12、 procedures developed by the American National Standards Institute (ANSI).This edition was approved by the ASSE Board of Directors on August 9, 2011 as an ASSE standard.Double Check Detector Fire Protection Backflow Prevention Assemblies vASSE 1048-2011Joseph FugeloProduct Standards Committee Chairm
13、anLabov Co.Philadelphia, PennsylvaniaRand AckroydRand Technical Consulting, LLCNewburyport, MassachusettsWilliam Briggs Jr.MGJ AssociatesNew York, New YorkMaribel CamposICC Evaluation ServicesWhittier, CaliforniaJudson CollinsJulyco ProfessionalsMannford, OklahomaRon GeorgePlumb-Tech Design and(b) D
14、ouble 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 (
15、2) properly located, tightly closing shut-off valves per Section 1.3.2.6 and properly located test cocks per Section 1.3.2.4. 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
16、Double Check Detector Assemblies consisting of two (2) or more complete DCDA or DCDA-II assemblies in parallel. The assemblies do not need to be of the same pipe size. The manifold size shall be identified by the single inlet and outlet of the manifold DCDA or DCDA-II assembly. Manifold Double Check
17、 Backflow Prevention Assemblies shall include line-sized shut-off valves on each inlet and outlet of the assemblies making up the manifold. 1.2.2 Size RangeConnection pipe sizes shall be in accordance with Table 1.2 Double Check Detector Fire Protection Backflow Prevention AssembliesASSE 1048-2011Ta
18、ble 1Rated Water Flow and Maximum Allowable Pressure Loss for Various SizesSize of DeviceRated FlowRPDA and(b) 3.6, Allowable Pressure Loss at Rated Flow.If the orientation of either of the checks or the bypass check(s) changes from the primary to an alternate orientation, the assembly shall also be
19、 tested to all of the following sections:(a) 3.5, Hydrostatic Backpressure Test of Checks;(b) 3.7, Bypass Flow Detection;(c) 3.8, Drip Tightness of First Check;(d) 3.9, Drip Tightness of Second Check; and(e) 3.10, Drip Tightness of Bypass Check (for DCDA-II Assemblies).2.2 Samples TestedThe testing
20、agency shall select one (1) of each type and model and size for the full test.2.3 DrawingsAssembly drawings and other data which are needed to enable a testing agency to determine compliance with this standard shall accompany assemblies when submitted for examination and performance testing under th
21、is standard.2.4 RejectionFailure of one (1) assembly shall result in a rejection of that type and model and size.2.5 Manifold AssemblyA manifold assembly shall be tested per Sections 3.2, Hydrostatic Test of Complete Assembly, and 3.6, Allowable Pressure Loss at Rated Flow. The individual assemblies
22、 that make up the manifold shall meet all of the test sections of the standard in their intended orientation based on the nominal pipe size for each individual assembly.Double Check Detector Fire Protection Backflow Prevention Assemblies 7ASSE 1048-2011Section III3.0 Performance Requirements and Com
23、pliance TestingNOTE: A failure due to dirt or debris is not cause for rejection. It is permissible to clean, but not replace fouled discs or seats during any test.3.1 Independence of Components3.1.1 PurposeThe purpose of this test is to determine that the shut-off valves and check valves operate wit
24、hout interfering with each other.3.1.2 ProcedureVerify that the shut-off valves and the check valves do not interfere with one another through their full range of travel.3.1.3 CriteriaAny interference of one (1) component with another component shall result in a rejection of the assembly.3.2 Hydrost
25、atic Test of Complete Assembly3.2.1 PurposeThe purpose of this test is to determine if the assembly withstands pressures of two (2) times the manufacturers maximum rated pressure without leakage or damage to the assembly.3.2.2 ProcedurePressurize the assembly through test cock #1 or #2 and hold a pr
26、essure of two (2) times the manufacturers maximum rated pressure for ten (10) minutes. The assemblys shut-off valves shall be in the full open position.3.2.3 CriteriaAny external leaks shall result in a rejection of the assembly.3.3 Seat Leakage Test for Shut-off Valves3.3.1 PurposeThe purpose of th
27、is test is to determine the shut-off valves capability to withstand a test pressure of two (2) times the manufacturers maximum rated pressure in the closed position without leakage.3.3.2 ProcedureNOTE: Non-integral shut-off valves shall be removed for this test.3.3.2.1 Procedures for the #1 Shut-off
28、 ValveWith the #1 shut-off valve in the closed position, slowly increase the pressure during a one (1) minute period on the inlet side from zero (0) psi to twice the manufacturers maximum rated pressure of the assembly. Hold the pressure for ten (10) minutes. Observe for leakage. Repeat the test, pr
29、essurizing the outlet side from zero (0) psi to twice the manufacturers maximum rated pressure of the assembly.8 Double Check Detector Fire Protection Backflow Prevention AssembliesASSE 1048-20113.3.2.2 Procedure for the #2 Shut-off ValveIf the sealing mechanism is different between the #1 shut-off
30、valve and the #2 shut-off valve, repeat Section 3.3.2.1 with the #2 shut-off valve.3.3.3 CriteriaAny evidence of leakage during the test shall result in a rejection of the assembly.3.4 Hydrostatic Backpressure Test of Bypass Check (for DCDA-II Assemblies)3.4.1 PurposeThis test is for assemblies whic
31、h incorporate a bypass check around the second check only. The purpose of this test is to determine if the check in the bypass line is capable of withstanding a backpressure of two (2) times the manufacturers maximum rated pressure without leakage or damage to the assembly.3.4.2 ProcedureWith the sh
32、ut-offs on the bypass closed and test cock #1 open, pressurize the bypass check through test cock #2 to two (2) times the manufacturers maximum rated pressure. Hold for ten (10) minutes.3.4.3 CriteriaAny leakage or indication of damage shall result in a rejection of the assembly.3.5 Hydrostatic Back
33、pressure Test of Checks3.5.1 PurposeThe purpose of this test is to determine if the checks can withstand pressures of two (2) times the manufacturers maximum rated pressure without leakage or damage to the assembly.3.5.2 Procedure - First CheckSeal the inlet and outlet of the assembly. The bypass li
34、ne shall be closed for this test. The assemblys shut-off valves shall be in the open position. Install a sight glass in test cock #2 upstream of the first check, purge the assembly of air. Open test cock #2 to the sight glass. Apply the test pressure at test cock #3. The height of the water in the s
35、ight glass shall be adjusted to be 6 inches (152 mm) above the top of the water space in the assembly. Raise the pressure at test cock #3 to twice the manufacturers maximum rated working pressure. Record the water level in the sight glass. Hold the pressure for ten (10) minutes.3.5.3 Procedure - Sec
36、ond CheckThe bypass line shall be closed for this test. Install the sight glass in test cock #3. Adjust the water level in the sight glass to be 6 inches (152 mm) above the top of the water space in the device. Apply a pressure through test cock #4 of twice the manufacturers maximum rated working pr
37、essure on the downstream side of the second check. Record the water level in the sight glass. Hold the pressure for ten (10) minutes.3.5.4 CriteriaAny leakage or indication of damage which prevents full compliance with the remainder of this standard shall result in a rejection of the assembly.Double
38、 Check Detector Fire Protection Backflow Prevention Assemblies 9ASSE 1048-20113.6 Allowable Pressure Loss at Rated Flow3.6.1 PurposeThe purpose of this test is to determine the pressure loss through the assembly at any flow from zero (0) GPM to the rated flow, and to determine if the pressure drop t
39、hrough the assembly generally increases from zero (0) flow to a flow of 50.00 GPM (3.15 L/s).3.6.2 ProcedureInstall the assembly per Figure 1 with a manometer or differential pressure gauge at gauge connections #1 and #2. These shall connect to ring piezometers per ISA 75.02. The supply source shall
40、 be capable of supplying a volume of water adequate to meet the flow requirements of the size of assembly on test and maintain an inlet pressure of at least 10.0 psi (68.9 kPa) greater than the allowable pressure loss at rated flow. The pressure loss through the piping between the shut-off valves of
41、 the assembly on test and the gauges at gauge connections #1 and #2 shall be subtracted from the differential pressure reading at gauge connections #1 and #2. Purge the system of air. The pressure loss at flow shall be measured at increments of 5.00 GPM (0.32 L/s), starting at zero (0) flow up to 50
42、.00 GPM (3.15 L/s). Gradually increase the flow of water through the assembly until the required rated flow of water is achieved, per Table 1. Increase the flow to 150% of the rated flow shown in Table 1 and record the differential pressure. Increase the flow to 200% of the rated flow shown in Table
43、 1 and hold for five (5) minutes; then record the differential pressure. Gradually decrease the flow of water to zero (0).Figure 1Test SetupTest Valve #1 Flow Meter (Location Optional) Gauge Connection #1 Gauge Connection #2Test Valve #3 Flow Meter Test Valve #4Test Valve #2NOTES:1. Gauge connection
44、s #1 the inlet and the outlet of the manifold shall identify its size. During the flow test, while still at 200% of flow, alternately close and open the shut-off valves of each of the assemblies in the manifold, causing the flow to pass through each assembly in the manifold individually for five (5)
45、 minutes.Install the assembly per Figure 1 with a manometer or differential pressure gauge at gauge connections #1 and #2. These shall connect to ring piezometers per ISA 75.02. The supply source shall be capable of supplying a volume of water adequate to meet the flow requirements of the size of as
46、sembly on test and maintain an inlet pressure of at least 10.0 psi (68.9 kPa) greater than the allowable pressure loss at rated flow. The pressure loss through the piping between the shut-off valves of the assembly on test and the gauges at gauge connections #1 and #2 shall be subtracted from the di
47、fferential pressure reading at gauge connections #1 and #2. Purge the system of air. The pressure loss at flow shall be measured at increments of 5.00 GPM (0.13 L/s), starting at zero (0) flow up to 50.00 GPM (3.15 L/s). Gradually increase the flow of water through the assembly until the required ra
48、ted flow of water is achieved, per Table 1. Increase the flow to 150% of the rated flow shown in Table 1 and record the differential pressure. Increase the flow to 200% of the rated flow shown in Table 1 and hold for five (5) minutes; then record the differential pressure. Gradually decrease the flo
49、w of water to zero (0).Double Check Detector Fire Protection Backflow Prevention Assemblies 11ASSE 1048-20113.6.4 Criteria (a) The occurrence of pressure loss greater than those shown in Table 1 at flows from zero (0) GPM to rated flow (both ascending and descending) shall result in a rejection of the assembly.(b) Failure of the pressure drop through the assembly to generally increase from static up to a flow of 50.00 GPM (3.15 L/s) with a maximum total downward deviation of 10% from the highest previous value at any point shall result in a rejection of the assembly.(c) Any d
