How to collect a water sample for metals testing
A clean, correctly collected sample is the difference between a defensible result and a do-over. Here's how to do it right for lead and metals by ICP.
1. Use the right container
Use the laboratory-supplied bottle. For metals, that's typically a pre-cleaned HDPE or polypropylene bottle. Do not rinse it, rinsing can remove the preservative or introduce contamination.
2. First-draw vs. flushed
For lead-in-water compliance (Lead & Copper Rule, school/childcare testing), collect a first-draw sample: water that has sat in the plumbing for at least 6 hours, taken before any other water is used that day. For distribution-system or general potability checks, a flushed sample (run the tap 30–60 seconds first) may be specified. Follow the protocol your program requires.
3. Collect the volume
Fill to the volume the lab requests (commonly 250–1000 mL depending on the analyte list). Open the tap gently to avoid splashing and fill smoothly.
4. Label and chain-of-custody
Label each bottle with the sample location and date/time of collection, and complete the chain-of-custody form. Note whether the sample is first-draw or flushed, the lab needs this to report against the correct standard.
5. Preserve and ship promptly
Keep samples cool (4°C) and submit them within the method hold time. Drop off Monday–Friday before 4 PM ET, or ship overnight with the completed chain-of-custody.
Need us to collect it?
Our certified field professionals handle water sampling on-site under chain-of-custody. See Field Science, or learn more about drinking water testing.