Dry-Heat Sterilization Process

Dry heat sterilization is one of the most practical and preferable forms of sterilization, using blown hot air to eliminate or deactivate all forms of life

the setting must be at 160 °C (320 °F) for a duration of two hours, 170 °C (340 °F) for one hour, and up to 190°C (375°F) for 6 to 12 minutes. These are typical cycle times, and depending on the specific application,

The heat that is passed onto the object is causing the denaturation of proteins on all bacterial spores, fungi, viruses, prions, and generally all forms of biological agents.

Advantages

• The heat can go deeply into thick objects, achieving an in-depth sterilization effect. Even objects inside packaging can be sterilized this way.
• Metallic objects that can handle heat well can be sterilized quickly at high temperatures.
• Dry heat is non-corrosive for metallic materials as it contains too little moisture.
• The process involves no toxic agents,.
• The object can be taken out and used almost immediately, as it cools down quickly

Disadvantages

• The dry heat can take much more time to achieve sterilization
• The heat can cause warping to sensitive materials or thin sheets.
• The high temperatures can irreversibly damage plastics, rubber, so these are not suitable for dry heat.
• Dray heat effect the chemical structure of some substance

Dry heat was actually one of the very first methods of sterilization, has highly predictable results, and can be modified to suit a wide range of different sterilization requirements.

Instruments and techniques used for dry heat sterilization include hot air ovens, incinerators, flaming, radiation, and glass bead sterilizers.

Read also:

• Moist Heat or Steam Sterilization Working Principle
• Difference between Sterilization and Depyrogenation

Resource Person: Ch/Ahmed Mahmoud