1、Laboratory Faucet Backflow Preventers 1ASSE Standard 1035 - 2008Performance Requirements forLaboratory FaucetBackflow PreventersAmerican Society of Sanitary EngineeringASSE Standard #1035-2008ASSE Board Approved: April, 2008ANSI Approved: September, 2009An American National StandardLaboratory Faucet
2、 Backflow Preventers iASSE Standard 1035 - 2008American Society of Sanitary EngineeringWestlake, OhioCopyright 2008, 2002, 1993, 1981All rights reserved.Neither this standard, nor any portion thereof, may be reproduced without the written consent of the American Society of Sanitary Engineering.No pr
3、oduct may be said to be ASSE approved unless the manufacturer has applied to ASSE, has had his product tested according to the applicable ASSE standard, and when the product has passed the test, displays the ASSE Seal on the product.Instructions for receiving the authorization to display the Seal ar
4、e available from ASSEs International Office. Organizations wishing to adopt or list 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.General Informationii Laboratory Faucet Backflow PreventersA
5、SSE Standard 1035 - 2008Laboratory Faucet Backflow Preventers iiiASSE Standard 1035 - 2008This foreword shall not be considered a part of the standard, however, it is offered to provide background information.ASSE standards are developed in the interest of consumer safety.The American Society of San
6、itary Engineering for Plumbing and Sanitary Research is dedi-cated to the preservation of public health and safety through “Prevention Rather than Cure”.Preventing potable water in plumbing systems from becoming contaminated or polluted is an important objective of ASSEs Standards Program. The progr
7、am addresses the development and promulgation of standards embracing performance criteria for manufactured plumbing components designed to safeguard public health and safety.Recognizing the probable sources or causes of contamination or pollution of a potable water system which can cause it to becom
8、e unfit or undesirable for human consumption is vital to the maintenance of its continued potability.Backflow prevention is essential for all laboratory water outlets because of the serious con-tamination potential existing there due to the real and/or potential cross connections present in laborato
9、ries. For this reason, this standard was developed to cover devices designed es-pecially for this service.This standard is one of a series of ASSE Backflow Preventer Standards, each of which cov-ers a different type of backflow protection device, each tailored to the protective requirements essentia
10、l to the specific system conditions in which it is installed and the degree of hazard involved.Although many of the material specifications are detailed within Section IV of this Standards, it is the responsibility of the manufacturer to comply with the requirements of the Safe Drink-ing Water Act,
11、United States Public Law 93-523.The working group which developed this standard revision, was set up within the framework of the Product Standards Committee of the American Society of Sanitary Engineering.Recognition is made of the time volunteered by members of this working group and of the support
12、 of the manufacturers who also participated in the meetings for this standard.This standard does not imply ASSEs endorsement of a product which conforms to these requirements.Compliance with this standard does not imply acceptance by any code body.Forewordiv Laboratory Faucet Backflow PreventersASSE
13、 Standard 1035 - 2008It is recommended that these devices be installed consistent with local codes by qualified and trained professionals.This standard was promulgated in accordance with procedures developed by the American National Standards Institute (ANSI).Laboratory Faucet Backflow Preventers vA
14、SSE Standard 1035 - 2008Edward LyczkoProduct Standards Committee ChairmanCleveland ClinicCleveland, OhioRand H. AckroydRand EngineeringNewburyport, MassachusettsGunnar O. CollinsCollins Backflow Specialists, Inc.Palatine, IllinoisJudson W. CollinsJULYCO ProfessionalsMannford, OklahomaShannon M. Corc
15、oran ASSE Standards CoordinatorWestlake, OhioA. Richard EmmersonGeneral InterestBuffalo Grove, IllinoisRon GeorgeRon George Design & ConsultingNewport, MichiganCharles GrossInternational Association of Plumbingand Mechanical OfficialsWalnut, CaliforniaSteven HazzardASSE Staff EngineerWestlake, Ohio2
16、007-08 Product Standards Committee John F. Higdon, P.E.Apollo Valves/Conbraco Industries, Inc.Pageland, South CarolinaValentine Lehr, P.E.Lehr AssociatesNew York, New YorkChuck LottPrecision Plumbing Products, Inc.Portland, OregonPeter MarzecUnited Association ofPlumbers and PipefittersWashington, D
17、.C.Brad NollWilkins, A Division of Zurn Industries, Inc.Paso Robles, CaliforniaThomas C. Pitcherello State of New JerseyBordentown, New JerseyShabbir RawalpindiwalaKohler CompanyKohler, WisconsinTsan-Liang Su, Ph.D.Center for Environmental SystemsStevens Institute of TechnologyHoboken, New Jerseyvi
18、Laboratory Faucet Backflow PreventersASSE Standard 1035 - 2008Table of ContentsSection I . 11.0 General . 11.1 Application 11.2 Scope . 11.3 Reference Standards 2Section II . 32.0 Test Specimens 32.1 Samples Submitted for Test 32.2 Samples Tested 32.3 Drawings 32.4 Rejection 3Section III 43.0 Perfor
19、mance Requirements and Compliance Testing 43.1 Hydrostatic Testing of Complete Device . 4Figure 1 43.2 Deterioration at Extremes of Manufacturers Temperature and Pressure Range . 53.3 Back Pressure of Downstream Check 53.4 Tightness of Checks . 53.5 Atmospheric Vent Valve Leakage . 63.6 Backflow Thr
20、ough the Inlet Check 6Figure 2 73.7 Backflow Through Outlet Check . 73.8 Atmospheric Vent Valve Leakage . 7Figure 3 8Figure 4 8Figure 5 83.9 Back Siphonage Back Pressure . 8Figure 6 93.10 Flow and Pressure Loss . 9Section IV 104.0 Detailed Requirements . 104.1 Materials . 104.2 Markings 114.3 Instal
21、lation and Mainenance Instructions 11Section V 125.0 Definitions. 12Laboratory Faucet Backflow Preventers 1ASSE Standard 1035 - 2008Performance Requirements for Laboratory Faucet Backflow PreventersSection I1.0 General 1.1 ApplicationLaboratory Faucet Backflow Preventers are designed to protect the
22、potable water supply from pollutants or contaminants which enter the system by backflow due to back siphonage or back pressure.1.2 Scope1.2.1 DescriptionThis standard applies only to those devices classified as backflow preventers that are designed for installation on laboratory faucets on the disch
23、arge side of the last shut-off valve. These devices are not for use under constant pressure conditions. These devices consist of two independently acting check valves, force loaded or biased to a normally closed position, and between the check valves a means for automatically venting to atmosphere,
24、force loaded or biased to normally open position. 1.2.2 Working PressureThe devices shall be designed for a minimum working pressure of not less than 125.0 psi (861.9 kPa).1.2.3 Temperature RangeThe devices shall be designed for flow temperatures between 33.0 F to 180.0 F (0.6 C to 82.2 C).1.2.4 Min
25、imum Flow CapacityThe device shall have a minimum flow capacity of 4.0 GPM (15.0 L/min) with a maximum pres-sure loss through the device of 20.0 psi (137.9 kPa).1.2.5 ConnectionsConnections shall be suitable for laboratory faucets. (Inlet and/or outlet connections are permit-ted to be different when
26、 required for special installations.)1.2.6 Flow Way Open AreaThe least total cross-sectional area of the air flow ways, including the seat area of the air vent valve, shall be not less than the least total cross-sectional area of the waterflow passage or passages upstream from the air vent valve. Th
27、e minimum cross-sectional dimensions of any air port or flow way, not including the valve lift, shall not be less than 3/32” (2.4 mm). These requirements shall be verified by the testing agency.2 Laboratory Faucet Backflow PreventersASSE Standard 1035 - 20081.2.7 Atmospheric Venta. The atmospheric v
28、ent shall be constructed so that it will open when the supply pressure is atmospheric or below.b. The atmospheric vent shall be constructed so that under a back pressure condition it will open.c. The atmospheric vent shall be constructed to provide vacuum breaking ability.1.2.8 Repairabilitya. The i
29、nternal parts of the device shall be accessible for inspection, repairs or replacements.b. All replaceable parts of the device of the same size and model shall be interchangeable with the original parts.1.3 Reference StandardsReference to industry standards shall be to the edition specified below. A
30、NSI/ASME B 1.20.1-83 Pipe Threads, General Purpose, (inch) ANSI/ASME B1.20.3-76 Dryseal Pipe Threads, (inch) CFR Title 21, Section 177 Food and Drugs: Indirect Food Additives: Polymers ANSI/ISA 75.02-96 Control Valve Capacity Test ProceduresLaboratory Faucet Backflow Preventers 3ASSE Standard 1035 -
31、 2008Section II 2.0 Test Specimens2.1 Samples Submitted for TestThree (3) devices of each size and model shall be submitted by the manufacturer. 2.2 Samples TestedThe testing agency shall select one (1) of each type or model and size for the full test. Tests shall be performed in the order listed on
32、 one (1) device.2.3 DrawingsAssembly drawings and other data which are needed to enable a testing agency to determine compliance with this standard, together with installation drawings, shall accompany devices when submitted for examination and performance tests under this standard.2.4 RejectionFail
33、ure of one (1) device shall result in a rejection of that type or model and size. 4 Laboratory Faucet Backflow PreventersASSE Standard 1035 - 2008Section III3.0 Performance Requirements and Compliance Testing3.1 Pressure Test of Complete Device3.1.1 PurposeThe purpose of this test is to determine if
34、 the device withstands pressures that equal two (2) times the minimum working pressure or the manufacturers rated working pressure, whichever is greater, without leakage or damage to the device.3.1.2 ProcedureInstall the device in the test system as in Figure 1. Admit water through the inlet of the
35、device allowing water to flow through it to purge it of air. Close the outlet valve and build up the supply pressure to the maximum required test pressure. Allow the device to stand under pressure for five (5) minutes and examine it for leaks.Figure 13.1.3 CriteriaAny leaks or indications of damage
36、shall result in a rejection of the device.Pressure reducing valveShut-off valveShut-off valveShut-off valveSupplyvalveShut-off valveFlow meterPressuregaugeBleeder valve & con-nection to hydrostatic testSight glassMinimum of42 inches (106.7 cm)Ring piezometer connection for dif-ferential pressure gau
37、geBack pressure supply valvePressure reducing valveRing piezometer connection for dif-ferential pressure gaugeDrainApproximately 10 diameters straight pipe.Device on TestLaboratory Faucet Backflow Preventers 5ASSE Standard 1035 - 20083.2 Deterioration at Extremes of Manufacturers Temperature Pressur
38、e Range3.2.1 PurposeThe purpose of this test is to evaluate the materials performance at extremes of manufacturers temperatures and pressures.3.2.2 ProcedureInstall the device with equipment capable of maintaining the manufacturers maximum rated temperature and pressure. Flow hot water through to th
39、e device on test at 2.0 GPM (7.6 L/min) continuously. Flow hot water through the device for eight hours per day for a total of ten days (80 hours). At the completion of 80 hours, run water maintained between 33.0 F and 40.0 F (0.6 C and 4.4 C) through the device for a minimum of one (1) hour.3.2.3 C
40、riteriaAny indication of change in the physical characteristics of the material which prevents full com-pliance with the remaining tests of this standard shall result in a rejection of the device.3.3 Back Pressure of Downstream Check3.3.1 PurposeThe purpose of this test is to verify the tightness of
41、 the downstream check when subjected to a back pressure equal to the rated working pressure.3.3.2 ProcedureThe inlet check valve shall be removed or mechanically held open, and the air vent shall be sealed closed. Install the device as shown in Figure 1, including the sight glass with the shut-off c
42、ock installed upstream of the inlet check valve. Purge the device of air. Close the supply valve, and open the shut-off cock to the sight glass. The height of the water in the sight glass shall be adjusted to 6.0 inches (152.4 mm) above the top of the water space in the assembly. Raise the pressure
43、downstream of the check valve to the minimum working pressure of the device and record the water level in the sight glass. Hold for five (5) minutes.3.3.3 CriteriaAny leaks of the check as indicated by a rise in the water level in the sight glass shall result in a rejection of the device.3.4 Tightne
44、ss of Checks3.4.1 PurposeThe purpose of this test is to determine if both checks are drip tight when subjected to a minimum pressure of 1.0 psi (6.9 kPa) on the upstream side with atmospheric pressure on the downstream side.3.4.2 ProcedureInstall the device as shown in Figure 1, including the sight
45、glass with the shut-off cock installed upstream of the inlet check valve. By suitable means, hold the downstream check valve par-tially open (fully clear of its seat). Purge the device of air and open the shut-off cock to the sight glass. With the downstream gate and throttling valve open, pressuriz
46、e the inlet to the device until there is flow from the outlet of the valve filling the sight glass column to at least 42.0 inches (1066.8 mm) measured from the center of the pipe line or the center of the check valve disc face (whichever is the shortest). Close the filling or supply valve tightly. H
47、old for five (5) minutes. Repeat on second check.6 Laboratory Faucet Backflow PreventersASSE Standard 1035 - 20083.4.3 CriteriaAny loss of level in the sight glass below 28.0 inches (711.2 mm) above the center of the pipe line, when horizontally mounted, or the center of the disc face, when vertical
48、ly mounted, shall result in a rejection of the device.3.5 Automatic Vent Valve Leakage3.5.1 PurposeThe purpose of this test is to verify the leak tightness of the atmospheric vent valve when the device is pressurized.3.5.2 ProcedureThe device shall be installed as in Figure 1 with a means for accura
49、tely measuring the rate of flow through the device. A pressure of 10.0 psi 1.0 psi (68.9 kPa 6.9 kPa) shall be maintained upstream of the supply valve. Open the inlet valve very slowly until the pressure in the inlet of the device is at the supply pressure.Repeat the test by opening the supply valve rapidly, within one (1) second maximum, at 10.0 psi (68.9 kPa). Repeat the tests with the supply pressure at 125.0 psi 1.0 psi (861.9 kPa 6.9 kPa) or the manufacturers maximum rated working pressure, whichever is greater.3.5.3 CriteriaAny leakage from
