1.1 本试验方法用于确定空气中细菌通过用于包装无菌医疗器械的多孔材料的途径。本试验方法旨在在可检测到细菌孢子通过试验材料的条件下对材料进行试验。 1.1.1 11个实验室参与了一项循环研究。每个实验室测试了六种商用多孔材料的重复样品，以确定对数折减值（LRV）（见第节中的计算） 12 ). 在本试验方法中描述的标准条件下测试的材料返回的平均值范围为LRV 1.7至4.3。 1.1.2 这项循环研究的结果表明，在比较测试数据和排名材料时，尤其是在使用少量样本复制时，应谨慎行事。 此外，进一步的协作工作（如实践中所述 E691 )应在该试验方法被视为足以设定性能标准之前进行。 1.2 本试验方法需要对微生物进行操作，只能由经过培训的人员进行。美国卫生和公共服务部出版物 微生物和生物医学实验室的生物安全 （CDC/NIH-HHS第84-8395号出版物）的指导意见。 1.3 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.4 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。 1.5 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 暴露室法是一种定量程序，用于在试验规定的条件下测定多孔材料的微生物屏障性能。从该测试中获得的数据有助于评估特定多孔材料相对于另一种多孔材料在导致包装内容物无菌损失方面的相对潜力。本试验方法不用于预测特定无菌环境中给定材料的性能- 包装应用。特定包装应用中的无菌维护将取决于许多因素，包括但不限于以下因素: 5.1.1 包装在分销和使用过程中会遇到的细菌挑战（微生物的数量和种类）。这可能受到运输方法、预期保质期、地理位置和储存条件等因素的影响。 5.1.2 包装设计，包括材料之间的粘附力、是否存在二次和三次包装以及包装内设备的性质等因素。 5.1.3 多孔包装在配送和保质期内遇到的空气交换速率和体积。这可能受到各种因素的影响，包括包装内的自由空气量以及由于运输、操作、天气或机械影响（如房间门关闭和HVAC系统）而产生的压力变化。 5.1.4 多孔材料的微观结构，影响在不同气流条件下吸附或捕获微生物或两者的相对能力。

1.1 This test method is used to determine the passage of airborne bacteria through porous materials intended for use in packaging sterile medical devices. This test method is designed to test materials under conditions that result in the detectable passage of bacterial spores through the test material. 1.1.1 A round-robin study was conducted with eleven laboratories participating. Each laboratory tested duplicate samples of six commercially available porous materials to determine the Log Reduction Value (LRV) (see calculation in Section 12 ). Materials tested under the standard conditions described in this test method returned average values that range from LRV 1.7 to 4.3. 1.1.2 Results of this round-robin study indicate that caution should be used when comparing test data and ranking materials, especially when a small number of sample replicates are used. In addition, further collaborative work (such as described in Practice E691 ) should be conducted before this test method would be considered adequate for purposes of setting performance standards. 1.2 This test method requires manipulation of microorganisms and should be performed only by trained personnel. The U.S. Department of Health and Human Services publication Biosafety in Microbiological and Biomedical Laboratories (CDC/NIH-HHS Publication No. 84-8395) should be consulted for guidance. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 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. 1.5 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 The exposure-chamber method is a quantitative procedure for determining the microbial-barrier properties of porous materials under the conditions specified by the test. Data obtained from this test is useful in assessing the relative potential of a particular porous material in contributing to the loss of sterility to the contents of the package versus another porous material. This test method is not intended to predict the performance of a given material in a specific sterile-packaging application. The maintenance of sterility in a particular packaging application will depend on a number of factors, including, but not limited to the following: 5.1.1 The bacterial challenge (number and kinds of microorganisms) that the package will encounter in its distribution and use. This may be influenced by factors such as shipping methods, expected shelf life, geographic location, and storage conditions. 5.1.2 The package design, including factors such as adhesion between materials, the presence or absence of secondary and tertiary packaging, and the nature of the device within the package. 5.1.3 The rate and volume exchange of air that the porous package encounters during its distribution and shelf life. This can be influenced by factors including the free-air volume within the package and pressure changes occurring as a result of transportation, manipulation, weather, or mechanical influences (such as room door closures and HVAC systems). 5.1.4 The microstructure of a porous material which influences the relative ability to adsorb or entrap microorganisms, or both, under different air-flow conditions.