【国外标准】 Standard Practice for Assessment of Rainwater Quality

4.1 As the world's population increases, so does the need for water to meet various needs. Rainwater harvesting offers a viable, sustainable approach to satisfying various water needs.4.1.1 Rainwater harvesting may be the only source of water supply for many rural and remote households where no other water supply is available. In urban and suburban locations, rainwater harvesting may help public water systems reduce peak demands and help delay the need for expanding water treatment plants.4.1.2 Rainwater harvesting can reduce storm water runoff, nonpoint source pollution, and erosion in urban environments.4.1.3 Rainwater harvesting provides for redundancies and diversified systems that decrease security issues associated with centralized facilities.4.2 An assessment of rainwater quality is necessary for determination of appropriate uses for water collected and stored in rainwater harvesting systems. This practice identifies a set of research and reporting requirements that will permit the intended user to assess the rainwater quality of a particular site.1.1 This practice provides a methodology for assessing rainwater quality.1.1.1 This practice identifies a set of research and reporting requirements that will permit the intended user to assess the rainwater quality of a catchment area of a particular site.1.1.2 This practice characterizes rainwater quality in general and identifies site conditions that may affect rainwater quality. Where site conditions affecting rainwater exist, additional assessment techniques may be required.1.1.3 Objectives guiding the development of this practice are (1) to synthesize and put in writing good commercial and customary practice for rainwater quality assessment; (2) to facilitate high quality, standardized water stewardship protocols; and (3) to clarify a standard of due diligence that is practical and reasonable.1.2 This practice does not establish design requirements for rainwater harvesting systems. However, it may provide information in support of decisions relative to design and implementation of rainwater harvesting projects.1.3 This practice does not identify use(s) of rainwater, commercial or otherwise. However, it may provide information in support of decisions relative to evaluation of property conditions and development options.1.4 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment.1.4.1 Water laws vary among governing jurisdictions. It is the responsibility of the user of this practice to determine regulatory requirements applicable to rainwater quality assessment and potential use(s).1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.