Trace2O AquaSafe WSL25 Plus, Инструкция по эксплуатации

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SECTION 4: SAMPLING
Rivers and streams
Take the sample as near as possible to the fastest flow – this will typically be found towards
the centre of the body of water. Avoid taking samples from too close to the bank, where the
water may be still and unrepresentative.
Care must be taken not to introduce floating debris, or solid matter from the banks of the
water course, into the water sample. Therefore, it may be preferable to attach the sampling
cable to the sterilised sampling cup and take the sample from a bridge or other overhanging
location. Alternatively, the cup may be cast out into the water from the edge and pulled slowly
and carefully back towards the operator.
Chlorinated drinking water
When storing samples of water in bottles for analysis at a later date, from sources that
contain residual chlorine, such as treated drinking water, the bottled sample must be
dechlorinated, i.e. the residual chlorine has to be removed to prevent further chlorination (and
killing of bacteria) whilst in transit.
To dechlorinate the water, the supplied sample collection bottles contain dechlorination
tablets.
N.B. If the sample is analysed immediately on-site, then it is not necessary to dechlorinate the
water.
Dechlorination
The dechlorination tablets are pre-placed inside each sample collection bottle.
Simply pull off the sterile seal, pour the sample from the sampling cup into the sample
collection bottle, seal and shake thoroughly to ensure thorough dissolving of the tablet.
The tablet will have no adverse effect on unchlorinated water.
Tap Samples
Turn on tap and allow water to flow for about 2 minutes, to flush the sampling pipeline.
Take an initial sample and carry out any appropriate on-site physical & chemical tests e.g.
Residual chlorine, turbidity, temperature & pH.
Take any other required physical and chemical samples.
Then disinfect the tap, which can be carried out in the two following ways:
Chemical Disinfection of Tap
Turn off the tap.
Squirt the inside of the tap with concentrated sodium hypochlorite solution (e.g. bleach), with
a wash bottle.
Leave for 3 minutes to disinfect fully.
Flush the tap until all the bleach has been washed off – this can be verified by taking further
residual chlorine tests.
Fill the prepared bacteriological sampling bottle (leave a slight air gap at the top) and seal the
lid tightly.