| Autoclaves were first invented by French | | | | When an autoclave is used for medical purposes |
| Microbioligist Charles Chamberland in 1879 who | | | | the idea is to sterilise reusable equipment so that |
| worked alongside Louis Pastuer who invented the | | | | bacteria, viruses and fungi are destroyed. |
| Patuerisation process. | | | | However protein prions like those associated with |
| The basic function of an autoclave machine is to | | | | CJD are able to withstand the usual 121 degree |
| pressurise aqueous solutions and heat them | | | | temperature and can still be active when. To kill |
| above their boiling point which will cause the | | | | protein prions a longer cycle and higher |
| solution to be sterilised as well as anything in the | | | | temperature is used (134 degrees Celcius). |
| solution. | | | | Due to the humid hot environment that is created |
| In order to create sterilisation using water you | | | | in an autoclave medical instruments made out of |
| need to be able to heat water past its normal | | | | some forms of plastic cannot be sterilised, but |
| boiling point. Under regular conditions water is not | | | | many small medical instruments are now single |
| able to be heated above 100degrees Celcius. | | | | use which eliminates this problem. |
| Further heating will not cause the liquid to rise in | | | | 2 common brands of small worktop autoclaves |
| temperature it simply boils the water. | | | | found in many dental surgeries and labs across |
| The solution to heating water beyond its normal | | | | the world are Prestige medical autoclaves and |
| boiling point is to heat it in a sealed container. This | | | | enigma autoclaves. In general there are 3 |
| happens because the pressure within the sealed | | | | methods that can be used to ensure that an |
| container increases as the water heats up, | | | | autoclave has reached the correct heating |
| causing the waters boiling point to increase due to | | | | temperature within the chamber and therefore |
| the amount of energy needed to form steam | | | | sterilisation has taken place. |
| increasing. | | | | Some medical packaging has a chemical indicator |
| Because air is very poor at steralising it needs to | | | | on it that changes colour once sterilisation has |
| be removed from the autoclave chamber first. | | | | occurred within the packaging. In some autoclaves |
| Different autoclaves remove air using different | | | | an alloy is present that will melt once the correct |
| methods. Some autoclaves use a vacuum pump | | | | temperature has been reached and in others a pH |
| to remove the air from the sterilisation chamber, | | | | sensitive chemical is present which will change |
| while others use a series of pressurisation and | | | | colour once the required conditions have been |
| depressurisation of the central chamber to create | | | | met. |
| airlessness. | | | | In addition to these indicators autoclaves have |
| Many different industries have uses for | | | | visible temperature sensors, pressure gauges and |
| autoclaves this includes: medicine, dentistry, | | | | times on the outside of the machine. |
| science, podiatry and body piercing. | | | | |