BS ISO 5667‑10:2020 pdf download.Water quality — Sampling Part 10: Guidance on sampling of waste water.
4 General aspects
4.1 Design of sampling programme
g is usually the first step in carrying out an investigation and largely determines the quality
of the whole investigation . It is therefore recommended that a detailed sampling strategy be drawn
up , often based upon a preliminary investigation in which an a
ment has identified the important
aspects . Both the purpose and the ambient situation determine the way in which the sampling is carried
out . General aspects for sampling programme design can be found in IS0 . 5667-1
4.2 Sampling point selection - Representativeness
g point selection should be
ntative of the waste stream to
mined . In so
this representativeness may be difficult to obtain because of the spatial and tempo
heterogeneity of the water body . It is necessary to carry out the sampling in the sections where the flo
is well mixed and homogeneous
The term " representativeness encompasses two notions depending on the type of environment
to be sampled :
representativeness in a flow ( canal , sewer , manhole , pressurised pipes , etc .
These two notions should be treated in different ways , but the goal remains to obtain a representative
Sampling points may be clearly identified ( by regulatory text ) or not .
ivestigation is recommended . This is generally the case for the
of se
By studying drawings of the sewer system initially , possible locati
be identified . Subsequently ,
Ite inspection should be conducted to ensure that the locations
ers and the path of the waste
stream corresponds to the drawings , and to make sure that the
orthe C me
epresentative f
the sampling purpose . The tracer studies may be a helpful tool
Each sampling point should be documented . It is important to gather , for example , the following
nformation : identification , location of the site , photos , geographical coordinates , site location , type o
flow ( open , closed ) , access conditions and sampling technique .
f necessary , specifically describe and label the sampling site . Select the site so that representative
samples can be obtained and the waste water flow ( with the exception of fixed sampling equipment ) is clearly visible from the sampling site .
4.3.2 Sampling time for effluent stream
The objective of a sampling programme often dictates when and how a sample is collected and is often determined by legislation or directives. Generally, when sampling sewages and effluents, it is normal to make allowances for the following sources of variation in quality:
a) diurnal variations (i.e. within-day variability);
b) variations between days of the week;
c) variations between weeks and months;
d) variations between seasons;
e) variations due to storm water episodes; and
f) trends.BS ISO 5667‑10 pdf download.