Question

3. Describe how an autoclave operates, and its purpose. Describe 3 limitations of an autoclave.

Answer 1

Autoclave is a pressurised device designed to heat aqueous solutions above their boiling point at normal atmospheric pressure to achieve sterilisation. Here the Auto means 'self' and clavis means 'self locking device'. The autoclave consists of following components 1. Hearing elements 2. Temperature controller 3. Pressure sensor. 4. Chamber 5. Door gasket 6. Solenoid valve. 6. Water level sensor. Most autoclave contain a sterilising chamber and sterilising jacket. Steam flows from sterilising jacket into sterilising chamber. Cool air is forced out. A special valve increases the pressure to 15 pounds/ square inch above normal atmospheric pressure. When the temperature raises to 121c and the superheated water molecules rapidly conduct heat into microorganisms. The time required to kill bacteria spores is 15 minutes.

Purpose of autoclave

The purpose of autoclave is to prepare materials for bacteriological cell cultures without contamination. It is also used for preparation of culture mediums.

Limitations

1.Somelastic materials melts in high heat, sharp instruments become dull

2. Many chemicals breakdown during the sterilisation process

3. Heating of large containers requires extra time.