1.1 这些测试方法描述了两种测量穿过建筑物围护结构的空气泄漏率的技术，这些围护结构可配置为单个区域。这两种技术都使用孔口鼓风机门在整个建筑围护结构上产生压差，并测量这些压差和产生的气流。压力差和气流的测量用于确定外壳的气密性和其他泄漏特性。 1.2 这些测试方法允许在减压和加压下进行测试。 1.3 这些试验方法适用于室内外温差小、风压低的情况；测量结果的不确定性随着风速和温差的增加而增加。 1.4 这些测试方法不测量正常天气和建筑物运行条件下的空气变化率。要直接测量换气率，请使用测试方法 电子741 . 1.5 这些测试方法的文本参考了提供解释材料的注释和脚注。这些注释和脚注（表和图中的注释和脚记除外）不应视为本标准的要求。 1.6 以国际单位表示的值应视为标准值。SI单位后括号中给出的值仅供参考，不被视为标准值。 1.7 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践，并确定监管限制的适用性。 有关具体危险说明，请参见第节 7. . 1.8 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《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 气密性- 建筑气密性是在正常天气和建筑运行条件下影响建筑换气率的一个因素。这些换气率占空间空调负荷的很大一部分，并影响乘员舒适度、室内空气质量和建筑耐久性。这些测试方法产生的结果表征了建筑围护结构的气密性。 这些结果可用于比较类似建筑的相对气密性，确定现有建筑改造措施的气密性改进，并预测空气泄漏。结合实践使用本标准 第1186页 允许识别同一建筑围护结构的不同部件的泄漏源和泄漏率。这些测试方法由测试方法演变而来 电子779 适用于孔口鼓风机门。 5.1.1 对自然条件的适用性- 在正常天气和建筑运行条件下，建筑围护结构的压力在围护结构上的不同位置之间变化很大，通常比测试期间的压力低得多。因此，使用这些测试方法的气密性测量不能解释为在自然条件下发生的自然渗透或空气变化率的直接测量。 然而，气密性测量可用于为自然渗透模型提供空气泄漏参数。这样的模型可以估计平均年通风率和相关的能源成本。试验方法 电子741 使用示踪气体稀释技术测量天然空气交换率。 5.1.2 与试验方法的关系 电子779 — 这些试验方法是对试验方法的具体修改 电子779 至孔口鼓风机门。对于无孔鼓风机门或对于太大而无法使用鼓风机门的建筑物，使用试验方法 电子779 . 5.1.3 与试验方法的关系 电子3158 — 这些测试方法适用于配置为单个区域的建筑物。对于多区域建筑的测试，使用测试方法 电子3158 . 5.2 单点法- 使用此方法提供空气泄漏估计，以评估气密性的改善。 5.3 两点法- 使用此方法可提供空气泄漏参数，用作自然通风模型的输入。两点法使用更复杂的数据分析技术，需要更精确的测量( 表X1.1和 X1.2英寸 )而不是单点法。它可用于估算建筑压力差低至4 Pa（0.016 in.H 2. O） （2）。建筑围护结构泄漏的各种参考压力已被用于或建议用于表征建筑气密性。这些压力包括4 Pa（0.016 in.H 2. O） ，10 Pa（0.04英寸高 2. O） ，30帕（0.12英寸高 2. O） ，和50 Pa（0.2英寸高 2. O） （2）。ASHRAE 基础知识手册 使用4 Pa。 5.4 减压与增压- 根据测试方法的目标，用户可以选择减压或加压或两者兼而有之。该标准允许进行减压和加压测量，以补偿两个方向的不对称流动。减压适用于测试建筑围护结构的密封性，包括防止渗透但在加压试验期间打开的回流挡板等项目的密封性。将减压和增压测量结果结合起来，可以最大限度地减少风和烟囱压力对气密性计算的影响，但可能会高估由于仅在增压下打开的回流风门造成的空气泄漏。 5.5 风和温差的影响- 在测试期间，平静的风和温和的温度可以提高精度和偏差。 由内外温差和风引起的包络线上的压力梯度，通过改变测试包络线上的建筑压力差（与不存在这些因素时的情况不同），导致测量偏差。风也会引起压力波动，影响测量精度并导致数据自相关。

1.1 These test methods describe two techniques for measuring air leakage rates through a building envelope in buildings that may be configured to a single zone. Both techniques use an orifice blower door to induce pressure differences across the building envelope and to measure those pressure differences and the resulting airflows. The measurements of pressure differences and airflows are used to determine airtightness and other leakage characteristics of the envelope. 1.2 These test methods allow testing under depressurization and pressurization. 1.3 These test methods are applicable to small indoor-outdoor temperature differentials and low wind pressure conditions; the uncertainty in the measured results increases with increasing wind speeds and temperature differentials. 1.4 These test methods do not measure air change rate under normal conditions of weather and building operation. To measure air change rate directly, use Test Method E741 . 1.5 The text of these test methods reference notes and footnotes that provide explanatory material. These notes and footnotes, excluding those in tables and figures, shall not be considered as requirements of the standard. 1.6 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard. 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. For specific hazard statements see Section 7 . 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 Airtightness— Building airtightness is one factor that affects building air change rates under normal conditions of weather and building operation. These air change rates account for a significant portion of the space-conditioning load and affect occupant comfort, indoor air quality, and building durability. These test methods produce results that characterize the airtightness of the building envelope. These results can be used to compare the relative airtightness of similar buildings, determine airtightness improvements from retrofit measures applied to an existing building, and predict air leakage. Use of this standard in conjunction with Practices E1186 permits the identification of leakage sources and rates of leakage from different components of the same building envelope. These test methods evolved from Test Method E779 to apply to orifice blower doors. 5.1.1 Applicability to Natural Conditions— Pressures across building envelopes under normal conditions of weather and building operation vary substantially among various locations on the envelope and are generally much lower than the pressures during the test. Therefore, airtightness measurements using these test methods cannot be interpreted as direct measurements of natural infiltration or air change rates that would occur under natural conditions. However, airtightness measurements can be used to provide air leakage parameters for models of natural infiltration. Such models can estimate average annual ventilation rates and the associated energy costs. Test Method E741 measure natural air exchange rates using tracer gas dilution techniques. 5.1.2 Relation to Test Method E779 — These test methods are specific adaptations of Test Method E779 to orifice blower doors. For nonorifice blower doors or for buildings too large to use blower doors, use Test Method E779 . 5.1.3 Relation to Test Method E3158 — These test methods are applicable for buildings that are configured as a single zone. For testing of multi-zone buildings, use Test Method E3158 . 5.2 Single-Point Method— Use this method to provide air leakage estimates for assessing improvements in airtightness. 5.3 Two-Point Method— Use this method to provide air leakage parameters for use as inputs to natural ventilation models. The two-point method uses more complex data analysis techniques and requires more accurate measurements ( Tables X1.1 and X1.2 ) than the single-point method. It can be used to estimate the building leakage characteristics at building pressure differences as low as 4 Pa (0.016 in. H 2 O). A variety of reference pressures for building envelope leaks has been used or suggested for characterizing building airtightness. These pressures include 4 Pa (0.016 in. H 2 O), 10 Pa (0.04 in. H 2 O), 30 Pa (0.12 in. H 2 O), and 50 Pa (0.2 in. H 2 O). The ASHRAE Handbook of Fundamentals uses 4 Pa. 5.4 Depressurization versus Pressurization— Depending on the goals of the test method, the user may choose depressurization or pressurization or both. This standard permits both depressurization and pressurization measurements to compensate for asymmetric flow in the two directions. Depressurization is appropriate for testing the building envelope tightness to include the tightness of such items as backdraft dampers that inhibit infiltration but open during a pressurization test. Combining the results of depressurization and pressurization measurements can minimize wind and stack-pressure effects on calculating airtightness but may overestimate air leakage due to backdraft dampers that open only under pressurization. 5.5 Effects of Wind and Temperature Differences— Calm winds and moderate temperatures during the test improve precision and bias. Pressure gradients over the envelope caused by inside-outside temperature differences and wind cause bias in the measurement by changing the building pressure differences over the test envelope from what would occur in the absence of these factors. Wind also causes pressure fluctuations that affect measurement precision and cause the data to be autocorrelated.