ISO 5667-14:1998 pdf download.Water quality一Sampling
1 Scope
This part of Iso 5667 provides guidance on the selection and use of various quality assurance techniques relating to the manual sampling of surface, potable, waste, marine and ground waters;
NOTE The general principles outlined in this part of ISO 5667 in some circumstances may be applicable to sludge and sediment sampling.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO 5667. At the time of publication, the editions indicated were valid. AllI standards are subject to revision, and parties to agreements based on this part of ISO 5667 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of Iso and IEC maintain registers of currently valid International Standards.
ISO 5667-1:1980, Water quality一Sampling 一Part 1: Guidance on the design of sampling programmes.
ISO 5667-3:1985, Water quality一Sampling 一Part 3: Guidance on the preseration and handling of samples.
3 Definitions
For the purposes of this part of ISO 5667, the following definitions apply.
NOTE Bias is the total systematic error as contrasted to random error. There may be one or more systematic error components contributing to the bias. A larger systematic difference from the accepted reference value is reflected by a larger bias value.
3.3 precision
closeness of agreement between independent results obtained under stipulated conditions [ISO 3534-1]
NOTE 1 The variation associated with test results from repeated sampling operations will be subject to variation from analytical sources as well as from sources connected with the sampling process. A comparison of random error from repeated sampling operations with that from repeated analysis of the same sample can be used to deduce the contribution of sampling to overall random error.
NOTE 2 Precision depends only on the distribution of random errors and does not relate to the true value or the specified value, (ISO 3534-1). The measure of precision is expressed in terms of a standard deviation value. Improved precision is reflected in a smaller standard deviation value.
NOTE 3 The "independence' of test results reflects the extent to which results are obtained in a manner not influenced by any previous result on the same test object (ISO 3534-1). Quantitative measures of precision depend critically on stipulated conditions. The well-known terms 'repeatability' and 'reproducibility' relate to specific types of stipulated conditions. The former term corresponds to measurements made under the same controlled (same method, strictly adhered to in the same laboratory) conditions; the latter term refers to the same method used in different laboratories.ISO 5667-14 pdf download.