Steam: the process involves exposing the equipment to dry saturated steam at a temperature of 73°C at atmospheric pressure for a minimum of 10 minutes. The low-temperature steam kills most vegetative microorganisms and some heat-sensitive viruses. This process can be used for breathing tubes, bite blocks, face masks and laryngoscope blades. The main advantages are that it is non-toxic, and less damaging to equipment. Its main disadvantage is that there is an increased risk of contamination because the equipment is wet.

Pasteurisation (hot water disinfection): this process involves immersing an object in boiling water for a specified time and temperature, for example, 70°C for 30 minutes. Boiling kills most non-spore-forming microorganisms, viruses and some heat-sensitive bacterial spores. The main advantage is that it is less damaging to equipment than autoclaving, and is non-toxic. However, heat may cause damage to some items.

Liquid chemicals: alcohols (ethanol or isopropanol), aldehydes (formaldehyde and glutaraldehyde) and oxidising agents (hydrogen peroxide) are used. The equipment must be cleaned beforehand to ensure good contact. It is then immersed in the liquid chemical for a specified period of time. The immersion time is dependent upon the chemical used and the level of disinfection required. Chemicals are advantageous because they have a broad spectrum disinfection range. However, they are potentially toxic, volatile and can cause damage to equipment.

Sterilisation is used for the complete destruction or removal of all microbial organisms, including viruses and bacterial spores, fungi and protozoa. The sterilisation process can involve the following.

Autoclaves: saturated steam under pressure is used to achieve complete destruction of all microorganisms. This requires direct contact between the equipment and the saturated steam, complete removal of air, and precise control of time, temperature and pressure. It is relatively fast, highly effective and non-toxic. However, it is unsuitable for heat and pressure sensitive equipment, such as fibre-optic endoscopes, and may cause corrosion of metal surfaces.

Dry air ovens: dry heat can be used to sterilise non-aqueous liquids, semi-solids (glycerine, oils and waxes), powders, needles and glass syringes. Typical times and temperatures required are 160°C for 2 hours, 170°C for 1 hour, and 180°C for 30 minutes. This process is neither toxic nor corrosive, but it is more time-consuming compared to the autoclave.

Ethylene oxide: gas sterilisation with ethylene oxide is usually carried out at 20°C to 60°C for 2–24 hours. Ethylene oxide can be used with or without a diluent gas (nitrogen or carbon dioxide). Sterilised items need to be aerated prior to use. Ethylene oxide is toxic and is unsuitable for use on ventilatory or respiratory equipment.

Gas plasma sterilisation: this uses a cloud of ionised gas containing reactive ions. Applying energy to certain gases such as hydrogen peroxide forms an ionised gas. The reactive ions interfere with cellular metabolism to cause sterilisation.

Radiation sterilisation: gamma radiation is used to sterilise equipment. The dose and time depend on the thickness and volume of the equipment. It requires expensive equipment.

Chemical: 2% glutaraldehyde can be used, but prolonged immersion times are required to achieve full sterilisation.