Secure waste air filtration in laboratory autoclaves Integrated water intrusion test to fulfil the requirements in the area of biotechnology

摘要

The thermal inactivation of natural or genetically modified micro-organisms is usually done in biological and medical laboratories in a steam sterilizer (autoclave) under defined parameters for pressure, temperature and time. The discharge of these organisms from the autoclave chamber - for example on the waste air or waste water path - must be prevented as a function of the risk group of the organisms [1, 2]. In particular in the course of the heating phase of the autoclaves, when the air is removed from the chamber and steam flows in, biological working substances can get into the workspace as aerosols. In practice, sterile filtration is often used for the inactivation of this waste air. For this purpose, the waste air is routed through hydrophobic membrane filters, completely removing its germ load from the waste air flow with proper handling. Sterile filtration can be associated with risks under certain conditions [3]. The filters have hitherto not been tested for their functionality (integrity), although this is technically basically possible and must be considered as necessary in terms of a risk assessment. On account of recent developments in the field of sub-statutory regulatory frameworks, changes are to be expected here [4]. The possible risks are hereinafter illustrated by means of practical example and the system design of a new test system, which was developed on the basis of the special requirements for integrity testing in laboratory autoclaves, will be presented.