A treatment indicator, a method for indicating a level of treatment in a treatment apparatus, and a method of preparing a treatment indicator are provided. The treatment indicator comprises a first body comprising a biological material, a fluid porous body in fluid communication with the first body in a fluid path, and a cleaning test soil disposed in at least a portion of interstitial spaces of the fluid porous body to inhibit traversal of a fluid through the fluid porous body to the first body via the fluid path.
