This standard covers diatomaceous earth (DE), perlite, and other disposable filter materials used to precoat filters for water supply service application. The purpose of this standard is to provide a guide for evaluating precoat filtration media. The criteria should be used to determine if such media is similar to the product currently being used to produce potable water in a specific water treatment plant or pilot project. Extensive use of DE and perlite by the water industry supports the need for this standard.