Standards Development

Scope

This document specifies the pretreatment required for sludge, treated biowaste, waste, sediment and soil (including soil-like materials), that are subject to the analysis of organic as well as inorganic chemical and physicochemical parameters. This document is applicable for the preparation of representative test portions from the laboratory sample that has been taken according to the sampling plan. Sampling is not part of this standard.

The pretreatment of samples aims at preparing a (small) test sample which is representative for the original sample.

This document describes the pretreatment under laboratory conditions (Clause 10).

For determining inorganic chemical and physico-chemical parameters this document describes procedures to prepare:

1. test samples of solid samples (10.2 and 10.5);

2. test samples of liquid sludge, liquid sediment and liquid waste (10.4 and 10.5).

For determination of organic compounds three pretreatment methods are specified for solid sludge, solid sediment, treated biowaste and soil:

1. a pretreatment method if volatile organic compounds are to be measured (see 10.3.2);

2. a pretreatment method if semi-volatile to non-volatile organic compounds are to be measured (see 10.3.3);

3. a pretreatment method if semi-volatile to non-volatile organic compounds are to be measured and the extraction procedure prescribes a field moist sample or if only indicative results are required (see 10.3.4).

The choice of the method depends above all on the volatility of the analyte. It also depends on the particle size distribution of the material (see Clause 10.1.2), the heterogeneity of the sample and the following analytical procedure.

Pretreatment procedures for the analysis of organic compounds in waste are described in 10.5.

Purpose

In laboratory practice, very often different analytical procedures have to be applied to the laboratory sample that has been taken according to the sampling plan. For this purpose, subsampling needs to be applied in such a way that the different test portions are representative for the original laboratory sample with respect to the compounds of interest and the specific analytical procedures. Ensuring the laboratory sample and test portions are representative is of major importance to guarantee the quality and accuracy of analytical results. The representativeness of the laboratory sample is specified by the sampling plan.

 At the moment, seven ISO and CEN standards describe procedures for the pretreatment of samples for environmental characterization. Namely, EN 15002:2015, EN 16179:2012, ISO 14507:2003, ISO 23909:2008, ISO 11464:2006, EN 17087:2019, ISO 167202005, under responsibility of CEN/TC 444, CEN/TC 351 and ISO/TC 190. This document, EN (ISO) 21744, is a merger of these seven standards and has been discussed with CEN/TC 351 and ISO/TC 190.