Hot air sterilizers vs. steam sterilizers

• Hot air sterilizers use hot air to sterilize objects. They operate at higher temperatures than steam sterilizers.
  They can be effective for sterilization, but some microorganisms may survive at the lower temperatures.
  Hot air sterilizers are often used in laboratories for glassware and metal instruments.
• Steam sterilizers use steam to sterilize items. They work at lower temperatures, which can be gentler on certain materials.
  They are generally more effective as steam allows for better heat transfer, ensuring more thorough sterilization.
  Steam sterilizers are widely used in medical facilities, especially for instruments and equipment that are sensitive to heat.

In medical practice, the admissibility of hot air sterilization is increasingly being viewed critically. Although this procedure is recognized if the devices have mechanical air movement, it does not meet all the requirements for the sterilization of 'critical' medical devices.

Section 4 (2) of the Medical Devices Operator Ordinance (MPBetreibV) refers to compliance with the recommendations of the Robert Koch Institute (RKI) on hygiene when reprocessing medical devices. According to point 2.2.4, the RKI prefers thermal sterilization processes with saturated steam (at 121 °C or 134 °C) due to their more reliable effectiveness.

The use of hot air sterilization is not explicitly prohibited, but RKI requirements, in particular for documentation and approval, can only be met to a limited extent with hot air sterilizers. A risk assessment in accordance with the RKI recommendation is required for medical practices, and the RKI recommends the use of steam sterilizers (autoclaves) for the reprocessing of 'critical' medical devices.

The MPBetreibVO (§ 4.2) requires the reprocessing of medical devices in accordance with the manufacturer's instructions using suitable validated procedures. The exact definition of a 'validated procedure' is not clear, but some experts interpret it as automatic documentation of sterilization procedures, while others understand it as a reproducible and error-resistant procedure.

The responsibility for reprocessing lies with the operator of the sterilizer, who must carry out a practice-specific risk assessment in order to select the appropriate sterilization procedure.