In the EPA's approved method of sampling equipment decontamination, which step follows the Non-phosphate Detergent wash?

• A. Physical Removal
• B. Tap Water Rinse
• C. Distilled Water Rinse
• D. Solvent Rinse

Answer: (B)

After the non-phosphate detergent wash, the next step is a tap water rinse. The detergent wash breaks up and removes soils, but it leaves detergent residues and loosened material on the surface. Rinsing with tap water flushes away most of that detergent plus the loosened debris, preparing the equipment for the finer rinses that follow. This rinse helps ensure that the subsequent distilled water rinse can work more effectively by not having to deal with detergent residues or heavy surface film. In the typical sequence, you’d then proceed to a distilled water rinse to remove minerals and any remaining contaminants, and only after that would a solvent rinse be used if the protocol calls for it. The core idea is to move from bulk cleaning to progressively purer rinses, and the tap water rinse is the logical immediate next step.