General Sampling Procedures
This summary document is designed to be used by personnel trained in the collection of
drinking water samples and handling of sample preservatives. Follow the procedures
described below to assist in the collection of an acceptable sample and to maintain the
integrity of the sample after collection.
1. Prepare a Sampling and Analysis Plan (SAP) which describes
the sampling locations, numbers and types of samples to be
collected, and the quality control requirements of the project.
2. Check with the laboratory before collecting samples to ensure
that sampling equipment, preservatives, and procedures for
sample collection are acceptable. It is best to obtain sampling
supplies directly from the laboratory performing the analyses.
Gather all equipment and supplies necessary for the project.
3. The acids and bases used in preservation of many types of
samples described in this document are dangerous and must
be handled with care. Always wear gloves and eye protection
when handling preservatives. When opening a preservative
bottle, particularly a glass ampoule, break open the ampoule
away from yourself and others. Have acid/base neutralization
supplies (baking soda) on hand in the event of a spill. If acid
spills on your skin or clothing, remove the contaminated
clothing and rinse the area with water. Do not apply baking
soda (the heat of reaction can cause burns).
4. Collect samples in an area free of excessive dust, rain, snow
or other sources of contamination.
5. Select a cold water faucet for sampling which is free of
contaminating devices such as screens, aeration devices,
hoses, purification devices or swiveled faucets. Check the
faucet to be sure it is clean. If the faucet is in a state of
disrepair, select another sampling location.
6. Collect samples from faucets which are high enough to put a
bottle underneath, generally the bath tub or kitchen sink,
without contacting the mouth of the container with the faucet.
7. Open the faucet and thoroughly flush. Generally 2 to 3
minutes will suffice, however longer times may be needed,
especially in the case of lead distribution lines. Typically the
water temperature will stabilize which indicates flushing is
completed. Once the lines are flushed, adjust the flow so it
does not splash against the walls of the bathtub, sink or other
surfaces.