Which standard method is NOT used for decontaminating equipment and materials?

• A. Lubricate equipment with petroleum products after cleaning
• B. Use high-pressure hot water wash
• C. Rinse with clean water
• D. Use approved chemical decontaminants

Answer: (A)

The main idea is that decontamination focuses on physically removing and inactivating contaminants to prevent cross-contamination, using cleaning, rinsing, heat washing, and approved chemical disinfectants. Lubricating equipment with petroleum products after cleaning isn’t a decontamination step; it leaves hydrocarbon residues and can harbor or spread microbes, potentially contaminating samples and the well environment. The other methods—high‑pressure hot water washing, rinsing with clean water, and using approved chemical decontaminants—are designed to remove or kill contaminants and ensure equipment is ready for safe, uncontaminated use.