The Principles of Medical Device Decontamination

the third and final stage commences.

The chamber is evacuated to a deep vacuum (typically <100mB) allowing the accumulated condensate in the chamber and load to evaporate and be removed, this is aided by the residual heat present in the load. At the end of sterilization the load is warm (not hot), dry and sterile. Table 10.2 below shows some typical temperature and time combinations which are used in moist heat sterilization.

Commonly used Time / Temperature relationships for Moist Heat Sterilization

Temperature ( o C)

Time (mins)

134

3*

132

4**

126

10*

121

15*

115

30***

*Recommended by the Medical Research Council 14

**Used in the USA

***Cited in British Pharmaceutical Codex, rarely used today

Table 10.2 - Temperature and time combinations used in moist heat (Saturated steam) sterilization processes.

Moist heat sterilization using saturated steam is typically used to sterilize the re-usable surgical instruments and other medical devices commonly used in a hospital surgical department.

In some healthcare settings aqueous fluids contained in flexible or rigid containers may also be sterilized by moist heat (in for example a pharmaceutical production unit).

101

@ 2025 Central Sterilising Club. All rights reserved. Do Not duplicate