Nebulisers
These are not to be confused with the humidifier that I have explained about above.
The idea of these is to turn water (often containing drugs) into a very fine mist of water, it is then often blown into the stream of air that the patient is breathing in. They are sometimes found in the patient tubes of ventilators, these are powered by gas from the ventilator. More often they are used during physiotherapy.
The normal way that the water is nebulised is by using a jet of air from a flow meter or from the ventilator itself. This makes a very compact unit.
A much larger type uses ultra sonics to shake the water into the very fine drops, these machines tend to be much larger, more expensive and obviously need electricity to power them. Maintenance on the gas powered ones will be limited to making sure that they are gas tight and that none of the tubes are blocked and there is a supply of gas at a suitable pressure. The ultra sonic ones will depend upon electronic repairs.
The frequency of sound used in the ultra sonic ones is around 30 kHz, (ultra sonic means above sound). If you have an electronic one you will have to electronically safety check it once a year.
The maintenance of medical equipment in developing countries. 