1.1 本指南介绍了制定长期监测（LTM）计划以监测建筑物中主动和被动蒸汽缓解系统性能时应考虑的因素。本指南还将有助于制定适当的性能标准，以确保蒸汽缓解系统仍然保护人类健康。多年来，在残留挥发性污染物留在地面的受污染土地上，主动和被动蒸汽缓解系统已被使用。本指南讨论了各种蒸汽缓解系统； 然而，其重点是制定蒸汽缓解系统的长期监测计划，该计划旨在保持多年不变。 1.2 LTM计划为蒸汽缓解系统提供了明确的性能目标，有助于减少潜在的混乱和无效的项目管理。LTM计划还定义了性能监测时间框架，以有效测试蒸汽缓解系统的有效性，而无需进行不必要且成本高昂的过度测试。这也将促进一致的监测。蒸汽缓解系统的安装通常没有充分考虑长期- 长期监测要求是必要的，以确保只要系统保持在适当的位置，它们就可以保护人类健康。本指南阐述了LTM计划的要求，以监测蒸汽缓解系统的持续有效性。蒸汽缓解系统正确安装的安装验证通常在受污染财产管理的补救设计阶段进行，本文件不包括。 1.3 本标准讨论了LTM计划的限制、约束和潜在误差源。 本指南不认可缓解系统供应商或蒸汽缓解系统的测试。然而，本指南确实为测试蒸汽缓解系统的通用程序和相关术语（视情况而定）提供了参考。 1.4 单位- 以国际单位制（SI）或英制单位表示的数值应单独视为标准。每个系统中规定的值可能不是精确的等效值；因此，每个系统应相互独立使用。将两个系统的值合并可能会导致不符合标准。 以国际单位制以外的单位报告试验结果不应视为不符合本标准。括号中给出的值仅供参考，不被视为标准值。 1.5 所有观察值和计算值应符合实践中确定的有效数字和舍入准则 D6026 . 为了将测量值或计算值与规定限值进行比较，应将测量值或计算值四舍五入到规定限值中有效数字的最近小数点。 1.6 本指南提供了有组织的信息收集或一系列选项，并不推荐具体的行动方案。本文件不能取代教育或经验，应与专业判断一起使用。并非本指南的所有方面都适用于所有情况。本ASTM标准不代表或取代必须根据其判断给定专业服务是否充分的谨慎标准，也不应在应用本文件时考虑项目的许多独特方面。 本文件标题中的“标准”一词仅表示该文件已通过ASTM共识程序获得批准。 1.7 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.8 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 蒸汽缓解系统有两种主要类型:主动和被动( 表1 ). 主动蒸汽缓解系统包括:子板降压（SSD）、子膜降压（SMD）、子膜增压、砌块墙降压、排水砖降压、建筑增压、热交换系统和室内空气处理。被动蒸汽缓解系统包括:被动通风、地板密封剂、蒸汽屏障和增加通风。蒸汽缓解系统也可能包括主动和被动技术的组合。 5.2 LTM计划的制定和实施对于确保缓解系统的长期保护性至关重要。 5.3 本指南中提出的方法是一种实用且简化的过程，用于确定长期监测要求、监测时间框架和确定何时不再需要使用蒸汽缓解系统所需的因素。 5.4 本指南旨在供环境专业人士使用，包括:安装蒸汽缓解系统、监测蒸汽屏障或制定蒸汽缓解系统LTM计划的顾问、建筑经理、当地或区域管理或监管机构。 蒸汽缓解系统安装和LTM活动只能由受过蒸汽缓解系统正确应用培训并在本指南所述监测方面有经验（如适用）的环境专业人员进行。 注1: 本标准产生的结果的质量取决于执行该标准的人员的能力，以及所用设备和设施的适用性。符合实践标准的机构 D3740 通常认为能够胜任和客观的测试/采样/检查等。 本标准的用户应注意遵守惯例 D3740 本身并不能保证可靠的结果。可靠的结果取决于许多因素；实践 D3740 提供了一种评估其中一些因素的方法。 （A） 初始验证（系统启动）-系统启动后的一段时间。 （B） 运行监控通过通常预期的年度条件验证系统是否在要求范围内运行所需的时间段。 （C） 系统退役期间的运行监测后的长期监测期。 （D） 附加测试如果系统出现问题或建筑物/系统发生变化，则可能需要采取这些措施。

1.1 This guide presents factors to consider when developing Long-Term Monitoring (LTM) Plans for monitoring the performance of both active and passive vapor mitigation systems in buildings. This guide will also assist in developing appropriate performance standards to make sure that vapor mitigation systems remain protective of human health. Active and passive vapor mitigation systems have been used for a number of years on contaminated properties where residual volatile contaminants remain in the ground. This guide discusses a variety of vapor mitigations systems; however, its focus is on the development of long-term monitoring plans for vapor mitigation systems that are designed to remain in place for multiple years. 1.2 A LTM Plan provides clear performance goals for a vapor mitigation system which help to reduce potential confusion and ineffective project management. The LTM Plan also defines performance monitoring time frames to efficiently test the vapor mitigation systems’ effectiveness without unnecessary and costly over-testing. This will also promote consistent monitoring. Vapor mitigation systems are often installed without adequate consideration of the long-term monitoring requirements necessary to make sure that they remain protective of human health for as long as the system remains in place. This guidance addresses the requirements of the LTM Plan to monitor a vapor mitigation system’s continued effectiveness. Installation verification that the vapor mitigation system was installed correctly is typically addressed in the Remedial Design stage of a contaminated Property Management and is not covered in this document. 1.3 LTM Plan limitations, constraints and potential sources of error are discussed in this standard. This guide does not endorse a mitigation system vendor or testing of vapor mitigation systems. However, this guide does provide a reference for the common procedures for testing vapor mitigation systems and related terms, as appropriate. 1.4 Units— The values stated in either International System (SI) units or English units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard. The values given in parentheses are provided for informational purposes only and are not considered standard. 1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026 . For purposes of comparing a measured or calculated value(s) with specified limits, the measured or calculated value(s) shall be rounded to the nearest decimal of significant digits in the specified limit. 1.6 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied with consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process. 1.7 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. 1.8 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. ====== Significance And Use ====== 5.1 There are two primary types of vapor mitigation systems: Active and Passive ( Table 1 ). Active vapor mitigation systems include: Sub-Slab Depressurization (SSD), Sub-Membrane Depressurization (SMD), Sub-Membrane Pressurization, Block-Wall Depressurization, Drain-tile Depressurization, Building Pressurization, Heat-Exchange Systems, and Indoor Air Treatment. Passive vapor mitigation systems include: Passive Venting, Floor Sealants, Vapor Barriers, and Increased Ventilation. Vapor mitigation systems may also consist of a combination of active and passive technologies. 5.2 Development and implementation of a LTM Plan is important for ensuring the long-term protectiveness of the mitigation systems. 5.3 The approach presented in this guide is a practical and streamlined process for establishing long-term monitoring requirements, monitoring time frames, and factors needed to determine when the use of a vapor mitigation system is no longer needed. 5.4 This guide is intended to be used by environmental professionals including: consultants, building managers, local or regional governing or regulatory agencies, that are installing vapor mitigation systems, conducting monitoring of the vapor barriers, or developing LTM Plans for vapor mitigation systems. Vapor mitigation system installation and LTM activities should only be carried out by environmental professionals who are trained in the proper application of vapor mitigation systems and experienced in the monitoring described in this guide, as applicable. Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors. (A) Initial Verification (System Startup)—Period of time immediately following system startup. (B) Operational Monitoring—Period of time needed to verify that the system is operating within requirements through typically expected annual conditions. (C) Long-Term Monitoring—Period of time following operational monitoring through system decommissioning. (D) Additional testing—These are actions that may need to be taken if there is a problem with the system or there is a change to the building/system.