Vermont Department of Health
Vermont drinking water lab certification, the Department of Health and NELAP.
Who certifies your lab in Vermont, why NELAP accreditation comes first, what the proficiency testing schedule requires, and what auditors look for in your initial calibrations.
At a glance
How drinking water lab certification works in Vermont.
Vermont is not a NELAP accreditation body, but its drinking water certification is built on NELAP. The Department of Health certifies labs that are already accredited to the TNI standards by a NELAP accreditation body.
Drinking water lab certification
- Program
- Drinking water laboratory certification, Vermont Department of Health. The Department also approves workplace drug testing labs, which is not an environmental program.
- Legal basis
- 18 V.S.A. § 501b, which lets the Commissioner certify labs that meet the National Environmental Laboratory Accreditation Conference standards in effect and hold NELAP accreditation or its equivalent. The Vermont Water Supply Rule requires public water system samples to be analyzed by the Department of Health laboratory or labs it certifies.
- Who needs it
- Labs analyzing samples from a public water system, and labs analyzing samples from non-public potable water sources for permitting under the Vermont Wastewater System and Potable Water Supply Rules.
- NELAP prerequisite
- Labs must be accredited to the TNI standards currently in effect by a NELAP accreditation body before the Department of Health will consider certification. The application asks for the current NELAP certificate and scope.
- Wastewater and other programs
- The Department of Health’s certification page describes drinking water certification and workplace drug testing approval. It does not describe a wastewater lab program.
- Out-of-state labs
- Vermont DEC states that the Department of Health is the certifying authority for both in-state and out-of-state labs. Out-of-state labs apply with the certificate and scope from their primary NELAP accreditation body.
- NELAP status
- Not a NELAP accreditation body as of October 2026, according to TNI’s list. Vermont relies on NELAP accreditation issued elsewhere as the basis for its own certificate.
The accreditation cycle
From application to renewal.
The steps below summarize the Department of Health’s certification page, application and proficiency testing guidance. Your certificate and Department of Health correspondence govern the specifics for your lab.
-
NELAP accreditation first
Obtain accreditation to the TNI standards from a NELAP accreditation body, then apply with the current certificate and scope, recent on-site assessment reports and your responses.
-
Apply by analyte and method
Select analytes and methods in the application’s four areas: microbiology, inorganic chemistry, organic chemistry and radiological chemistry.
-
Proficiency testing
A minimum of two PTs a year with no more than seven months between results, reported directly by the PT provider. Reports sent by the lab are not accepted.
-
Assessment and renewal
The Department of Health may conduct an on-site assessment or accompany another accrediting body, at the lab’s cost. Renewal materials are due at least 30 days before expiration.
Initial calibration
What auditors check in your initial calibrations.
Vermont has no separate calibration rule. Its certificate rests on NELAP accreditation to the TNI standard and on the Water Supply Rule’s analytical requirements, mostly EPA methods from 40 CFR Part 141, so assessors work from the same questions as any TNI program.
A range that brackets what you report
The lowest standard should sit at or below your reporting limit and the highest at or above the top concentration you report. Results outside the calibrated range need to be qualified.
Error at the low end, not r² alone
A correlation coefficient of 0.999 can still hide a low standard that back-calculates 30 percent off. Auditors look at relative error, especially at the lowest levels.
Records that rebuild the curve
Raw responses, the model and weighting used, any excluded points with the reason, and the verification that followed. An auditor should be able to reconstruct every initial calibration from the record.
TNI accreditation and EPA methods underneath
Vermont certifies labs that meet the NELAC standards and hold NELAP accreditation, and its Water Supply Rule sets analytical requirements by reference to 40 CFR Part 141, except for six PFAS covered in Section 6.12. Your calibration criteria come from that TNI quality system and from each approved method.
Source: 18 V.S.A. § 501b(a); Vermont Water Supply Rule §§ 6.1.3 and 6.12; 40 CFR Part 141
The Department of Health asks for copies of on-site assessment reports and your responses since your last Vermont renewal. Calibration findings from your primary NELAP assessment are part of the file it reviews.
Self-check
Are your initial calibrations ready for a Vermont assessment?
Tick what your lab could show an auditor today. Nothing you select is saved or sent anywhere.
6Checks to work through
Select each item your lab could show an auditor today.
A self-assessment to help you prepare, not a compliance determination.
Vermont specifics
In Vermont, NELAP accreditation comes first.
Vermont does not accredit labs to the TNI standard itself. The statute lets the Commissioner certify a lab that meets the National Environmental Laboratory Accreditation Conference standards and is accredited by an approved NELAP accrediting authority or its equivalent. In practice the lab earns NELAP accreditation elsewhere and then applies to Vermont with its certificate, scope and recent on-site reports.
That makes the primary NELAP assessment the main test of your calibration practice. The Department of Health may conduct its own on-site assessment or join another accrediting body, and it reviews the on-site reports and corrective action responses you submit. Most methods are the EPA drinking water methods in 40 CFR Part 141 that the Water Supply Rule adopts; for six PFAS, the rule sets its own analytical requirements in Section 6.12.
The rules continue to change. Vermont DEC lists a current Water Supply Rule effective January 1, 2026, replacing the version dated February 24, 2024. The Department of Health’s proficiency testing guidance requires at least two PTs a year, no more than seven months apart, with results sent by the provider.
How WLTR helps
Calibration evidence ready for a Vermont certification review.
WLTR independently reviews the calibration your instrument software produced. Your analyst still makes the final call. What changes is that the evidence is complete, consistent across analysts, and ready before the auditor asks for it.
- Each analyte reviewed one at a time in the instrument software.
- The model and weighting are whatever the batch was processed with.
- r² is the number most people look at, even though it does not measure error at the low end.
- QA signs off without an independent check on the curve.
- Every analyte and every candidate model side by side in the Calibration Intelligence dashboard.
- Diagnostics run automatically and the best fit curve is identified, with the reasons recorded.
- Relative error at every level, including the lowest standard, shown on one screen.
- A traceable record your QA manager can review, sign and hand to a Vermont Department of Health assessor.
See how your own ICAL data looks when every analyte and model is laid out for review.
Questions
Vermont accreditation FAQs
Is Vermont a NELAP state?
No. The Vermont Department of Health is not a NELAP accreditation body. It does, however, require labs to hold NELAP accreditation to the TNI standards before it will consider drinking water certification.
Who certifies drinking water labs in Vermont?
The Vermont Department of Health, under 18 V.S.A. § 501b. Vermont DEC states that the Department of Health is the certifying authority for both in-state and out-of-state labs.
Does Vermont certify wastewater labs?
The Department of Health’s certification page describes drinking water certification and workplace drug testing approval, and does not describe a wastewater lab program. Its drinking water certification also covers non-public potable water samples analyzed for permitting.
What proficiency testing does Vermont require?
According to the Department of Health’s PT guidance, a minimum of two PTs a year for each field where a PT is readily available, with no more than seven months between results. The PT provider must send the reports, and the lab needs at least two acceptable PTs out of the past three attempted.
Does Vermont have its own initial calibration rule?
The certification statute and the Department of Health’s program pages do not set calibration criteria. Calibration requirements come from the TNI standard behind your NELAP accreditation and from the approved methods: the EPA methods in 40 CFR Part 141, plus Water Supply Rule Section 6.12 for six PFAS.
Sources
Primary sources for this page.
- Vermont Department of Health, laboratory certification programs (opens in a new tab)
- 18 V.S.A. § 501b, certification of laboratories (Vermont Legislature, unofficial copy) (opens in a new tab)
- Vermont Department of Health, drinking water certification application (opens in a new tab)
- Vermont Department of Health, proficiency testing FAQs (opens in a new tab)
- Vermont DEC, certified labs (opens in a new tab)
- Vermont DEC, drinking water laws and regulations (opens in a new tab)
- Vermont Water Supply Rule, final proposed rule filed with LCAR, October 2025 (opens in a new tab)
- TNI, NELAP recognized accreditation bodies (opens in a new tab)
This page summarizes public program information to help labs prepare. Requirements change, and the agency’s current rules and guidance always take precedence. WLTR is not affiliated with or endorsed by the Vermont Department of Health. Spot something out of date? Tell us at admin@wltr.tech.
Before your next assessment
See your Vermont ICALs the way an assessor will.
Bring a recent initial calibration. We will walk you through every analyte and candidate model in the Calibration Intelligence dashboard, the best fit, and the record your QA manager would sign.
Request a demoHow the methodology works
Running environmental methods? See how WLTR works for environmental testing labs and water and wastewater utility labs.