EPA 537 Sampling Instructions

 (Click here to view these instructions as a PDF)

Contact us with any questions before sampling.  Samples will be rejected if improperly submitted.

Clearly label each sample container. Use a permanent marker (Sharpie or similar) to indicate the sampling location and the date and time collected.

Use the proper container to collect your sample and do not rinse out any preservatives present. Specific sample containers are required for all EPA 537 analyses. Samples will be rejected if collected in the incorrect container and will require re-sampling. If you have any questions, please contact us before sampling (208-883-2839 [Moscow] or 509-838-3999 [Spokane]).

Refrigerate samples or place samples on ice immediately after sampling prior to shipping to lab. Samples must be submitted to the lab within 48 hours of sampling.  EPA 537 protocols have strict preservation and temperature requirements thus samples must arrive at the laboratory cold (< 10oC) and in the correct containers or samples will be rejected.

Before submitting your samples to the lab, complete a chain of custody form for each entry point (EP).


EPA 537 requires field blanks to be prepared while collecting samples at each sampling site.

EPA 537:  Perfluorinated Alkyl Acids in Drinking Water 

Bottles: 250 mL polypropylene plastic (two bottles for each entry point)

Fill the bottle under a slow stream of water until the bottle is filled up to the neck. Gently replace the cap, tighten securely, and invert the sample a few times to dissolve the preservative.

Field Blanks (required for each entry point):

You will have one sealed 250 mL plastic bottle that contains preserved, reagent water (labeled Reagent Water) and one plastic bottle that is empty (labeled Field Blank).  At the sampling site, open the bottle containing reagent water and pour it into the empty bottle, replace the cap securely and ship it with the samples.