Which of the following standards outlines labeling and declarations for pre/post consumer recycled content?

The correct standard that outlines labeling and declarations for pre/post consumer recycled content is ISO 14021. This standard specifically deals with environmental claims, providing guidelines for companies regarding the creation and use of labels and declarations related to recycled content in products.

ISO 14021 is focused on self-declared environmental claims, including those about recycled content, which is essential in ensuring that consumers have access to reliable information about the sustainability qualifications of materials. By utilizing ISO 14021, manufacturers can effectively communicate the amount of pre-consumer and post-consumer recycled materials in their products, which is critical for transparency and accountability in environmental marketing.

The other standards listed have different focuses. For instance, ISO 14025 addresses Type III environmental declarations, which are based on Life Cycle Assessment (LCA) information, while ISO 14040 deals with the principles and framework for conducting LCA. ISO 21930 specifically targets sustainability declarations for buildings and other built environment products, but it does not concentrate on the labeling for specific recycled content the same way that ISO 14021 does.