Under what condition can used materials be reused?

Used materials can be reused if they meet the code requirements for new materials because building codes are designed to ensure safety, structural integrity, and performance standards for all construction materials. These codes establish specific criteria that materials must adhere to in order to be deemed acceptable for use in new construction or renovation projects. If a used material can demonstrate compliance with these code requirements—such as being structurally sound, free from significant wear or damage, and suitable for its intended function—it can be considered safe for reuse.

Other options, while they may have some relevance, do not necessarily ensure that the reused materials meet the stringent requirements set forth by building codes. For example, approval by the building official or the fact that materials are recycled does not automatically imply they meet the specific code criteria applicable to new materials. Similarly, simply being cleaned does not guarantee that they abide by the necessary structural or safety standards, which is fundamental for any material being incorporated into a project.