Microbiological testing

A 500ml sample in a sterilised plastic bottle is required for this analysis (sterilised bottles are provided by the laboratory on request).

Samples should be taken at the supply and at various taps in the distribution system (see sampling techniques below).  All samples must be chilled to 4°C (except those to be analysed for Amoeba) and should arrive within 24 hours of collection.  Labeleach bottle with the Location, Date and Time.

NB:     

1. Do not rinse the sample bottle prior to sampling.
2. The cap of the bottle should not be placed lid down at any point neither should fingers come into contact with the underside of the lid.
3. It is helpful to leave a small air space in the bottle to facilitate mixing by shaking before examination.     

Sampling techniques

1. Taps. When sampling from a tap, open fully and let water run to waste for 2-3 minutes or for a time sufficient to permit clearing of the service line.  Reduce the flow to permit filling the bottle without splashing.  If tap cleanliness is questionable apply a solution of Sodium Hypochlorite (100mg/L) or flame the faucet before sampling. Let water run for an additional 2-3 minutes after treatment.  If sampling from a hot/cold tap, run hot water for 2 minutes then cold water for 2-3 minutes and collect samples as above. 
2. Reservoires(eg: Tanks, Swimming Pools, Cooling Towers, etc) Hold the closed bottle near its base and plunge it below the surface.  Remove the top and turn the bottle until its neck points slightly upward and mouth is directed toward the current.  If there is no current, create one by pushing the bottle forward away from the hand.  Replace cap before pulling the sample out.