Certified labs by state

CDC and EPA both say to use a state-certified laboratory for drinking-water tests. Certification is a state job. EPA publishes contacts for each state’s certification program. That page is the root of this directory.

Inventory pages tell you how to use the official search and list labs that publicly take private-well work. Inventories now include Pennsylvania, Florida, Maine (arsenic is common in Maine wells — see Arsenic in Maine well water) , and Iowa (nitrate is common in Iowa wells — see Nitrates in Iowa well water) . If bacteria or nitrate fails, the next reader of the report is the health department, not a filter brand.

State pages on this site

What “certified” means

States accredit environmental laboratories for fields of accreditation: a matrix (drinking water), a method, and an analyte. A lab can be excellent at wastewater metals and useless for drinking-water coliform. Ask for the analyte.

NELAP is a national standard some states use. State-only accreditation can be just as real. What you want is current drinking-water accreditation for the tests on your order form.

How not to use a directory

• Do not treat a listing as a current certificate. Accreditation lapses.
• Do not pick the cheapest coliform and assume metals are included.
• Do not send a treatment salesperson’s unlabeled printout as your annual test.
• Do not ignore a present coliform because an iron number looks fine.

This site is not medical, legal, or engineering advice. Bacteria or nitrate results belong with your health department.