Which statement about glass bead sterilizers is true?

• A. Beads heat up to 120°C and sterilize large metallic tools in 30 minutes.
• B. Beads heat up to 140°C and sterilize plastic items in 5 minutes.
• C. Beads heat up to 130°C and only take 1-10 minutes for small metallic tools.
• D. Beads heat up to 130°C and sterilize large metallic tools in 20 minutes.

Answer: (C)

Glass bead sterilizers work by heating glass beads to a high temperature, then transferring that heat quickly to small metal instruments. The key idea is that a short, high-heat exposure can sterilize small tools efficiently. The temperature around 130°C is typical for this method, and for small metallic instruments the required exposure time is brief—often within 1 to 10 minutes. This makes sense because the goal is rapid heat transfer to kill microbes without long processing times.

The other statements aren’t consistent with how glass bead sterilizers are used. Heat at 120°C would be lower than usual and the claim about sterilizing large metallic tools in 30 minutes isn’t practical for this method, which is designed for quick treatment of small items. Using 140°C is not standard, and plastics aren’t suitable for this method due to the risk of melting or deformation. A 20-minute exposure for large tools also doesn’t match typical practice, since the system is intended for short durations with small instruments.