Course info

Commonly used sample collection techniques

 1.    Grab Sample

• Used to describe the collection from a sample tap.

 2.    Subsurface sample

• Used to describe the collection from a treatment basin

 3.    Composite sample

• Samples that are collected and poured into a common container over a specified period of time.
• This type of sample collection is not acceptable for bacteriological analysis.  You cannot determine the extent or time of a single contamination event during the collection period.