Introduction

When performing microbiological examinations, it is especially important
a) that only the micro-organisms which are present in the sample are isolated or enumerated;
b) that the micro-organisms do not contaminate the environment.

In order to achieve this, it is necessary to pay attention to personal hygiene and to use working techniques that ensure, as far as possible, aseptic conditions.

Since in this International Standard, it is possible to give only a few examples of the precautions to be taken during micro-biological examinations, a thorough knowledge of microbiological examinations and of the micro-organisms involved is essential.

Ultimately, it is the analyst who should judge whether manipulations are safe and can be considered to be good laboratory practice.

Many manipulations may, for instance, unintentionally lead to cross-contamination and the analyst should always verify the accuracy of the results given by his technique.

In order to be able to perform examinations correctly, it is necessary to take certain precautions when constructing and equipping a laboratory. A number of such precautions are referred to in clause 4.

Certain precautions have to be taken not only for the sake of hygiene but also to ensure good reproducibility of results. It is not possible to specify all precautions to be taken in all circumstances, but the principal measures to be taken during the preparation, sterilization and storage of media and apparatus are described in clause 5.

If the guidance given in this International Standard is observed, this will also contribute to the protection of the health of personnel. For further information on this subject, reference should be made to the documentation listed in the bibliography, and in particular to references [1], [2] and [3].

Reference

• ISO 6887, Microbiology - General guidance for the preparation of dilutions for microbiological examination.
  
  

Download the complete Standard Method immediately after purchase!