Which of the following items cannot be disinfected?

• A. Emery board
• B. Nail clipper
• C. Glass file
• D. Metal forceps

Answer: (A)

Porous surfaces can’t be properly disinfected. Emery boards are made of a porous, abrasive material that traps moisture and debris in tiny crevices, so chemical disinfectants can’t reach all microbes. That makes thorough disinfection unreliable, so they’re handled as disposable items and discarded after each use.

Glass files and metal instruments like nail clippers and forceps are non-porous, so they can be thoroughly cleaned and either disinfected or sterilized for repeated use. This is why the emery board is the one that cannot be adequately disinfected.