What is the most effective and safest sterilization technique?

• A. Steam under pressure
• B. Boiling water
• C. Dry heat
• D. Chemical sterilants

Answer: (A)

Moist heat under pressure is the most reliable way to achieve true sterilization. The autoclave uses steam at high pressure, so the heat is transferred to every surface quickly and deeply. That combination—moist heat plus pressure—kills all forms of microorganisms, including heat‑resistant spores, on instruments and wrapped packs. Because the cycle times are practical and the steam cleans and penetrates easily, sterilization is achieved consistently when the cycles are properly run (for example, around 121°C for about 15 minutes for many loads, with adjustments for different materials).

Steam sterilization is also safer in daily use because it avoids chemical residues and minimizes exposure to hazardous substances. In contrast, boiling water can disinfect but doesn’t reliably kill spores; dry heat needs much higher temperatures and longer times and isn’t as versatile for many items; chemical sterilants pose chemical exposure risks and require careful handling and rinsing. Therefore, steam under pressure stands out as the most effective and practical sterilization method for a wide range of instruments.