A 11 ID 3 07EflS2 NATL INST OF STANDARDS & TECH R.I.C. )ly A1 11 03072852 International Sympos/Water supply and dr QC100 .U57 N0.553, 1979 C.1 NBS-PUB-C 19 je in Buildings NBS Special Publication 553 NATIONAL BUREAU OF STANDARDS The National Bureau of Standards' was established by an act of Congress on iMarch 3, 1901. The Bureau's overall goal is to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the Nation's physical measurement system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau's technical work is per- formed by the National Measurement Laboratory, the National Engineering Laboratory, and the Institute for Computer Sciences and Technology. THE NATIONAL MEASUREMENT LABORATORY provides the national system of physical and chemical and materials measurement; coordinates the system with measurement systems of other nations and furnishes essential services leading to accurate and uniform physical and chemical measurement throughout the Nation's scientific community, industry, and commerce; conducts materials research leading to improved methods of measurement, standards, and data on the properties of materials needed by industry, commerce, educational institutions, and Government; provides advisory and research services to other Government agencies; develops, produces, and distributes Standard Reference Materials; and provides calibration services. The Laboratory consists of the following centers: Absolute Physical Quantities 2 — Radiation Research — Thermodynamics and Molecular Science — Analytical Chemistry — Materials Science. THE NATIONAL ENGINEERING LABORATORY provides technology and technical ser- vices to the public and private sectors to address national needs and to solve national problems; conducts research in engineering and applied science in support of these efforts; builds and maintains competence in the necessary disciplines required to carry out this research and technical service; develops engineering data and measurement capabilities; provides engineering measurement traceability services; develops test methods and proposes engineering standards and code changes; develops and proposes new engineering practices; and develops and improves mechanisms to transfer results of its research to the ultimate user. The Laboratory consists of the following centers: Applied Mathematics — Electronics and Electrical Engineering 2 — Mechanical Engineering and Process Technology 2 — Building Technology — Fire Research — Consumer Product Technology — Field Methods. THE INSTITUTE FOR COMPUTER SCIENCES AND TECHNOLOGY conducts research and provides scientific and technical services to aid Federal agencies in the selection, acquisition, application, and use of computer technology to improve effectiveness and economy in Government operations in accordance with Public Law 89-306 (40 U.S.C. 759), relevant Executive Orders, and other directives; carries out this mission by managing the Federal Information Processing Standards Program, developing Federal ADP standards guidelines, and managing Federal participation in ADP voluntary standardization activities; provides scientific and technological advisory services and assistance to Federal agencies; and provides the technical foundation for computer-related policies of the Federal Government. The Institute consists of the following centers: Programming Science and Technology — Computer Systems Engineering. 'Headquarters and Laboratories at Gaithersburg, MD, unless otherwise noted; mailing address Washington, DC 20234. ; Some divisions within the center are located at Boulder, CO 80303. AU6 17 1979 Water Supply and Drainage no ^53 in Buildings Proceedings of an International Symposium September 28-30, 1976 National Academy of Sciences Washington, D.C. Editors Lawrence S. Galowin JoAnne R. Debelius Center for Building Technology National Engineering Laboratory National Bureau of Standards Washington, D.C. 20234 In cooperation with: Counterpart Commission W-62 U.S. National Committee for the International Council for Building Research, Studies and Documentation Building Research Advisory Board Commission on Sociotechnical Systems National Research Council U.S. DEPARTMENT OF COMMERCE, Juanita M. Kreps, Secretary Luther H. Hodges, Jr., Under Secretary Jordan J. Baruch, Assistant Secretary for Science and Technology NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director Issued August 1979 Library of Congress Catalog Card Number: 79-600105 National Bureau of Standards Special Publication 553 Nat. Bur. Stand. (U.S.), Spec. Publ. 553, 232 pages (Aug. 1979) CODEN: XNBSAV U.S. GOVERNMENT PRINTING OFFICE WASHINGTON: 1979 For sale by the Superintendent of Documents. U.S. Government Printing Office, Washington, D.C. 20402 Stock No. 003-003-02101-6 Price $6 (Add 25 percent additional for other than U.S. mailing). PREFACE In the United States, the process by which plumbing systems are planned, designed, constructed, and operated is highly regulated by prescriptive (as contrasted with performance) codes and standards and largely comprises the specification, assembly, installation, and opera- tion of materials and equipment offered by a diversity of manufacturers. Because the process revolves about products—fixtures, fittings, or trim (often referred to as brass), specialty items, and pipe—technological developments that have been and continue to be made are mainly product- oriented and the result of proprietary research and development activ- ities of manufacturers. These proprietary activities benefit from and are constrained by research performed in furtherance of the development of plumbing codes and standards. The broader and more basic research has traditionally been centered at the National Bureau of Standards and augmented by programs at a limited number of universities such as the Stevens Institute of Technology, the University of Iowa, the University of Illinois, Pennsylvania State University, Massachusetts Institute of Technology, Johns Hopkins University and Virginia Polytechnic Institute. With each new product or product-oriented advance or systems inte- gration in a building there is growing awareness by those involved in plumbing (and by informed outsiders) that the current process of plan- ning, designing, constructing, and operating plumbing systems does not (a) engage the expertise of all the scientific areas that, in actuality, comprise the basis of plumbing, (b) provide a valid basis for comparing objectives and economics of competitive development, (c) focus innovative efforts on potentially exploitable developments, and (d) facilitate exploitation of developments. This awareness is being heightened by recent drought experiences and broadened concerns of the availability of water and energy and the complexity and cost of waste water or by-product disposal. Given this widening interest in, and national need not only for improving the state of the art of- plumbing but also for improving the integration of considerations relating to plumbing with those relating to other building and utility concerns, the Counterpart Commission, in cooperation with the CIB W-62, decided that it would be useful to convene an international symposium. The meeting theme was directed at improving the description of plumbing research needs defined earlier by the Counterpart Commission , to place those needs in perspective ¥is-a-vis other building and utility research needs, and to suggest a general plan of action for research activity. In preparation for the symposium, the Counterpart Commission had a series of theme papers prepared by subcom- mittees of its members and other knowledgable specialists which could provide the framework for discussion at the symposium. iii The topics of primary concern identified from the United States perspective were submitted in the following position papers: 1 . Water Requirements and the Procedures for Estimating the Demand for Water in Buildings The most widely used procedure for estimating the demand for water within buildings is the probabilistic method developed by Dr. Roy Hunter while at the National Bureau of Standards. The Hunter method provides an estimate of the number of fixtures most likely to be operating simultaneously as a function of the total number of fix- tures in the design. In developing this technique for real systems, Hunter departed from a rigorous probabilistic approach and substi- tuted equivalency factors (fixture units). It is believed that the computational complexity of the true probabilistic approach was one of the reasons why Hunter developed the fixture unit concept. The advent of the modern digital computer removes this restraint. The Hunter technique and values assigned to the parameters have changed little since their establishment 35 years ago, and in view of their recent experiences in large-scale building projects, engineers have begun questioning the accuracy of this method. The results of several studies indicate that significant potential savings, in both initial costs and operating costs, can be achieved with an accurate knowledge of the demand for water within buildings. This position paper discusses alternative mathematical models, the nature and extent of a field data acquisition program, the human factor element, and the preparation of a design guide.