1.1 本指南提供了一种计算和证实成品包装纸和纸板产品回收含量的方法。由于目前没有可用的物理或化学测试方法来确定成品纸的绝对回收含量，因此建议制造商使用质量平衡方法。计算基于时间加权平均流量，该流量基于供给成分流量和一致性。推荐的计算方法包括按批次或按特定等级或类似等级的时间加权平均。 不建议通过数学分配而不是实际纤维含量来分配平均回收含量。也就是说，如果随着时间的推移使用了50%的再生纤维，则为时间加权平均值。人们不能用同样的数据来报告50%的产品是100%回收的。 1.1.1 百分比计算基于磅/吨或千克/吨，时间范围受机器和坡度限制（见 10.1.1.1 和 10.1.1.2 ). 1.1.2 这些计算中未使用制浆和回收率。 成品中再生纤维含量的计算仅是配料流中纤维类型、流量和所考虑时间段的函数。 1.2 本指南涵盖( 1. )含有任何数量或种类再生纤维的包装纸和纸板产品的再生含量；和( 2. )计算和证实买卖双方协议中声称的再生纤维含量水平的方法。 1.2.1 当回收的非纤维材料（例如填料）是回收纤维配料的一部分时，本指南可在修改或不修改的情况下用于计算或证实包装纸和纸板产品的回收含量。 对本指南的适当修改提供了有限的指导，以确定纸制品中回收非纤维材料的数量。 1.3 本指南不建议使用一定量或某种再生纤维或材料，因为( 1. )包装纸或纸板产品中回收成分的数量和种类应由买方和卖方商定，以及( 2. )建议的计算和证明程序可用于买卖双方约定的任何数量或种类的回收材料。 1.4 本指南推荐的质量平衡计算方法可能符合也可能不符合适用的联邦、州或地方法律，用于消费者收到的回收含量声明。对内容声明的指导有限 附录X1 . 1.5 以下安全隐患警告仅适用于试验方法部分第节 10 ，在本指南中: 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。 1.6 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。

1.1 This guide provides an approach for both the calculation and the substantiation of recycled content of finished packaging paper and paperboard products. A mass balance approach is recommended for use by manufacturers since no physical or chemical test method is currently available to determine absolute recycled content of a finished paper product. Calculations are based on time weighted average flows which are based on furnish component flow rates and consistency. Recommended approaches to the calculations include by batch or by time weighted average for a specific grade or similar grades. It is not recommended that average recycle content be allocated by mathematical apportionment rather than by actual fiber content. That is, if 50 % recycled fiber is used over time that is the time weighted average. One cannot use this same data to report 50 % of the production is 100 % recycled. 1.1.1 Percentage calculations are based on lb/ton or kg/tonne with the time frame constrained by machine and grade (see 10.1.1.1 and 10.1.1.2 ). 1.1.2 Pulping and recycling yields are not used in these calculations. The calculations of recycled fiber content in the finished product is solely a function of type of fibers in the furnish flows, the volume of flow and the time period considered. 1.2 This guide covers ( 1 ) recycled content of packaging paper and paperboard products that contain any amount or kind of recycled fiber; and ( 2 ) methods to calculate and substantiate the level(s) of recycled fiber content claimed by an agreement between the buyer and the seller. 1.2.1 This guide may be used with or without modification to calculate or substantiate the recycled content of packaging paper and paperboard products when recovered nonfibrous materials (for example, filler) are a part of the recycled fiber furnish. Limited guidance is provided for appropriate modifications to this guide for the determination of amount of recycled nonfibrous materials in paper products. 1.3 This guide does not recommend either an amount or a kind of recycled fiber or material to use since ( 1 ) the amount and kind of recycled content in a packaging paper or paperboard product should be agreed upon between the buyer and the seller, and ( 2 ) the calculation and substantiation procedures recommended may be used for any amount or kind of recycled material agreed upon between the buyer and the seller. 1.4 The mass balance calculation method recommended by this guide may or may not comply with applicable federal, state, or local laws for recycled content statements intended to be received by consumers. Limited guidance on content statements is in Appendix X1 . 1.5 The following safety hazards caveat pertains only to the test method portion, Section 10 , of this guide: 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. 1.6 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.