- Use sterile container with sodium thiosulfate added to neutralize residual chlorine or other halogen.
- Hold samples at <10º C, but not frozen, during collection and transit.
- Complete the chain of custody (COC) form provided. Note date and time of collection.
- Use waterproof pen to label bottle with sample location, description, date and time.
Potable Water (Drinking Water)
- Open tap fully and let water run to waste for 2–3 min, or for a time sufficient to permit clearing the service line. (If tap cleanliness is questionable, choose another tap or disinfect the faucet [inside and outside] with a bleach solution prior to sampling; let water run for an additional 2 to 3 min after treatment and before sampling.)
- Reduce flow to permit filling the bottle without splashing.
- Fill the bottle (≥120 ml), leaving ample air space in bottle.
- Take samples from a river, stream, lake or reservoir by holding the bottle near its base in the hand and plunging it, neck downward, below the surface.
- Turn bottle until neck points slightly upward and mouth is directed toward current. If there is no current, create a current by pushing bottle forward horizontally in direction away from hand.
- Fill the bottle (≥120 ml), leaving ample air space in bottle. If collecting samples from more than one reservoir, it is recommended that disposable gloves be worn and changed after each sample.
Recreational waters include freshwater swimming pools, spas, and naturally occurring fresh and marine waters. Collect samples during periods of maximum bather load.
- Collect samples by removing cap and holding bottle near the base at an angle of 45º. Fill in one slow sweep down through the water, with the mouth of the bottle always ahead of hand. Avoid contamination of sample by floating debris.
- Fill the bottle (≥120 ml) and replace cap.
Storage and Handling
- Drinking water for compliance testing: hold samples at <10° C, but not frozen, once collected and during transit to laboratory.
- Quantitative: deliver samples to laboratory on same day within six hours of collection in cooler with wet ice.
- Presence / Absence: chilled samples can be shipped overnight with holding time until analysis not exceeding 30 hours.
Other water types for noncompliance testing:
- Keep samples at <10° C, but not frozen, during transport on cold pack and until time of analysis.
- Ship chilled samples with frozen cold packs overnight for next day delivery to analyze within 24 hours of collection.
- Place chilled samples inside thermal pouch with frozen cold packs.
- Seal thermal pouch and place in box.
- Place completed Chain of Custody in plastic document holder and pack in box outside of thermal shipping pouch.
- Ship overnight Monday–Thursday only for morning delivery to: Special Pathogens Laboratory, 1401 Forbes Avenue, Suite 401, Pittsburgh, PA 15219
Questions? Call 412-281-5335.