Division 1 Sampling

The basic requirement is to obtain a representative and homogeneous laboratory sample.

The analyst shall ensure that samples do not become contaminated during sample preparation. Containers have to be rinsed with high purity acetone or hexane (p.A., HLPC grade or equivalent) before use to minimise the risk of contamination. Wherever possible, apparatus coming into contact with the sample shall be made of inert materials e.g. glass or polished stainless steel. Plastics such as polypropylene are to be avoided, because the analyte can adsorb onto these materials.

All of the sample material received by the laboratory is to be used for the preparation of test material. Only very finely homogenised samples give reproducible results.

There are many satisfactory specific sample preparation procedures which may be used.