1.1 本指南涵盖了在易腐产品（如食品和药品）上非侵入性外包装使用的商用时间-温度指示器（TTI）的选择信息。当连接到易腐产品的包装上时，TTI用于测量产品的组合时间和温度历史，以预测产品的剩余保质期或发出其可用保质期结束的信号。易腐产品的加工商有责任确定产品在适当温度下的保质期，并与指示剂制造商协商，选择与产品质量最匹配的可用指示剂，作为时间和温度的函数。 注1: 除了时间-温度指示器，TTI也是时间-温度监视器和时间-温度积分器的缩写。 1.2 时间-温度指标可以整合到危害分析和关键控制点（HACCP）计划中。对于指示器指示可用保质期结束或产品在正常储存温度下达到保质期的产品，应制定适当的搬运说明。 1.3 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。 1.4 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====== 3.1 易腐产品的包装上通常标明保质期，以表明其保质期的推定结束。由于大多数易腐产品的保质期取决于温度，因此通过假设产品在其整个使用寿命内保持在规定的温度范围内来确定有效期。这种方法的一个问题是，无法确定产品的保质期是否因暴露在较高温度下而缩短。 当连接到封装时，时间-温度指示器解决了这个问题，因为当暴露在更高的温度下时，它会更快到达终点。 3.2 为了直接指示保质期结束，时间-温度指示器特性应尽可能与产品的质量特性相匹配。当产品保持在标准存储温度时，指示器应在产品保质期的同时达到其终点。此外，为了确定在其他温度下匹配的准确性，应了解产品和指示剂的保质期随温度的变化。 阿伦尼乌斯关系是描述保质期随温度变化的一种常见且方便的方法。在不适用的情况下，可以建立产品的单个时间-温度点，并获得与TTI的近似相关性。 3.3 当连接到易腐产品的包装上时，时间-温度指示器可能会补充或在某些情况下替换到期日期代码。TTI的添加为易腐产品在其保质期内提供了更高的置信度，因为它对产品暴露的实际温度条件做出了响应。 3.4 就最低限度加工的冷藏食品而言，即使在消费者明显看到产品质量恶化之前，高温下病原菌的快速生长也可能对健康构成严重危害。在这种情况下，到期日可用于在标准温度下储存，而阈值温度TTI用于指示暴露在可测量生长的温度下。也可以使用双功能TTI，在这种情况下，标准TTI将指示在正确存储温度下的保质期，而阈值- 温度部分表示暴露在更高的温度下。

1.1 This guide covers information on the selection of commercially available time-temperature indicators (TTIs) for noninvasive external package use on perishable products, such as food and pharmaceuticals. When attached to the package of a perishable product, TTIs are used to measure the combined time and temperature history of the product in order to predict the remaining shelf life of the product or to signal the end of its usable shelf life. It is the responsibility of the processor of the perishable product to determine the shelf life of a product at the appropriate temperatures and to consult with the indicator manufacturer to select the available indicator which most closely matches the quality of the product as a function of time and temperature. Note 1: Besides time-temperature indicator, TTI is also an abbreviation for time-temperature monitor and time-temperature integrator. 1.2 Time-temperature indicators may be integrated into a Hazard Analysis and Critical Control Point (HACCP) plan. Appropriate instructions should be established for handling products for which either the indicator has signaled the end of usable shelf life or the shelf life of the product at its normal storage temperature has been reached. 1.3 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. 1.4 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 ====== 3.1 Expiration dates are often marked on the packages of perishable products to indicate the presumed end of their shelf lives. Since the shelf lives of most perishable products are temperature dependent, the expiration date is determined by assuming the product will be kept within a prescribed temperature range for its entire life. A problem with this method is that there is no way to determine if the shelf life of a product has been shortened by exposure to a higher temperature. A time-temperature indicator solves this problem when attached to the package because it reaches its end point sooner when exposed to a higher temperature. 3.2 In order to directly indicate the end of the shelf life, the time-temperature indicator characteristics should be matched as closely as possible to the quality characteristics of the product. When kept at the standard storage temperature for the product, the indicator should reach its end point at the same time as the product's shelf life. In addition, to determine the accuracy of the match at other temperatures, the change of shelf life with temperature should be known for both the product and the indicator. The Arrhenius relationship is a common and convenient method of describing the change of shelf life with temperature. In cases where it is not applicable, individual time-temperature points for the product may be established and an approximate correlation with the TTI obtained. 3.3 When attached to the package of a perishable product, a time-temperature indicator may supplement, or in some cases replace, the expiration date code. The addition of a TTI provides a greater level of confidence that the perishable product is within its shelf life because it responds to the actual temperature conditions to which the product has been exposed. 3.4 In the case of minimally processed refrigerated foods, the rapid growth of pathogenic bacteria at elevated temperatures may pose a serious health hazard even before the deterioration of the quality of the product becomes apparent to the consumer. In this case, an expiration date may be used for storage at the standard temperature, while a threshold-temperature TTI is used to indicate the exposure to temperatures at which growth becomes measurable. It is also possible to use a dual-function TTI, in which case the standard TTI would indicate the shelf life at the correct storage temperature while the threshold-temperature part would indicate the exposure to higher temperatures.