ASTM D 5663 : 2025

1.1This guide aids in calculating and substantiating recycled content in paper-based packaging products. Mass balance/material balance is used, since no established physical-test method is available to date which measures the recycled content of any paper product. Calculations are based on time weighted average flow rates and consistencies, measured at paper and paperboard mills, by batch/time weighted average, for a specific grade or similar grades. It is not correct to use this method to allocate the average among portions of the batch’s recycled content. For example, if 50 % recycled fiber is used for production over time, then 50 % is the time weighted average. It is not legitimate to use the same data to report that 50 % of the production is 100 % recycled.

1.2This guide covers: recycled content of packaging paper and paperboard products that contain any amount or kind of recycled fiber, and methods to calculate and substantiate the level(s) of recycled fiber content claimed by an agreement between the buyer and seller.

1.3This guide does not recommend either an amount or a kind of recycled fiber or material. The calculation and substantiation procedures may be used for any amount or kind of recycled material. The amount and kind of recycled content in a product should be decided by agreement between the buyer and seller.

1.4The mass balance calculation method recommended by this guide may or may not comply with applicable federal, state, or local laws about recycled content statements intended for consumers. Some guidance on recycled content statements is in Appendix X1.

1.5This standard pertains only to calculations and contains no safety hazards.

1.6This 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.