In many cases for water testing specially E-coli Test of Colform bacteria test Results not seems to be satisfying as there is some how a minute mistake can ruin up your whole sample and you will not get accurate results,this is because inappropriate sampling, so today we will discus the simplest procedure to take sample for microbiology testing.
Step 1:
Spray spirit on your hands up to arms for disinfection purpose.
Step 2:
Remove any attachments from the tap such as pipes, filter etc.open the tap for 5 minutes to flush out the standing water, close the tap and cleas with tissue paper. Spray a small quantity of spirit on surface of the tap and flame it with match stich and let it cool down.
Step 3:
After flaming, open the tap again to turn the water down to thin stream (about the width of a pencil) and let it run for one minute.
Step 4:
To avoid contamination while taking the sample, hold the bottles near the bottom with one hand, hold the top of the cap with other, then unscrew the cap. Do not plance tha cap on the ground.sampling will be more reliable if preformed near flame.
Step 5:
Hold the bottle under the stream of water, being careful not to let the bottle touch the sample tap, Fill the bottle to the neck (leave 1″ from top) but do not allow it to over flow Remove the bottle from the water flow and replace the cap.
Step 6:
Label the bottle with permanent marker and kept it in isolated ice box having sterilized coolants (under controlled conditions of 4*c) Sample should be delived to laboratory as soon as possible.
*Pre-Sterilized sampling bottles of at least 100-500 ml capacity made of pre-sterilized disposible/autoclavable plastics should be used for water sampling.