New Hampshire NH ELAP
New Hampshire environmental lab accreditation, NH ELAP and the TNI standard.
Who accredits your lab in New Hampshire, which standard you are assessed against, how out-of-state labs qualify, and the calibration section New Hampshire wrote into its own rule.
At a glance
How environmental lab accreditation works in New Hampshire.
New Hampshire is a NELAP state. TNI lists the New Hampshire Department of Environmental Services as a NELAP accreditation body accrediting to the 2016 TNI Standard, as of October 2026.
NELAP accreditation body
- Program
- New Hampshire Environmental Laboratory Accreditation Program (NH ELAP), New Hampshire Department of Environmental Services. NH ELAP provides primary accreditation to in-state and out-of-state labs.
- NELAP status
- Listed by TNI as a NELAP accreditation body, accrediting to the 2016 TNI Environmental Laboratory Sector Standard, as of October 2026
- Legal basis
- RSA 485:44 and RSA 485:46; accreditation rules in Env-C 300, readopted with amendments by Document #13291, effective November 23, 2021
- Quality system standard
- Env-C 301.03 states that references to the TNI standards are to the 2016 edition. DES states that NH ELAP currently accredits labs according to the 2016 TNI Standards.
- Who needs it
- RSA 485:44 requires accreditation for any lab testing public water supply compliance, and for environmental analyses in New Hampshire for other governmental purposes where accreditation is specified. DES states that labs used for regulatory PFHxS, PFNA, PFOS and PFOA drinking water analysis must be accredited by NH ELAP. Env-C 300 also covers labs that seek accreditation voluntarily.
- Matrices
- Potable water (drinking water), non-potable water, solid and chemical materials, including SW-846 methods, biological tissue, and air and emissions
- Out-of-state labs
- DES grants secondary accreditation to out-of-state labs based on the accreditation granted by their primary accreditation body. Under Env-C 303.15 it recognizes the same matrix, method and analyte combinations it accredits, and analyte groups only if identical to its own.
The accreditation cycle
From application to renewal.
The steps below summarize Env-C 300 and the NH ELAP program page. Your certificate and NH ELAP correspondence govern the specifics for your lab.
-
Apply for primary or secondary accreditation
Primary accreditation is based on the results of the on-site assessment and the lab’s participation in proficiency test studies. Out-of-state labs applying for secondary accreditation include a copy of any assessment report not more than 2 years old (Env-C 303.15).
-
Proficiency testing
At least 2 PT studies per year as required by Volume 1, Module 1 of the TNI standards, plus at least one successful PT study each year for each drinking water method and analyte the lab seeks accreditation for (Env-C 307.01).
-
Assessments
Env-C 300 defines a reassessment as a biennial assessment similar in scope to an initial assessment, with surveillance assessments as needed in between. Where DES is the primary body, reported changes that affect day-to-day operations trigger an assessment within 60 calendar days.
-
Annual renewal
Accreditation is valid for one year from the date of initial issuance (Env-C 304.01), and the renewal application must reach the department before the current accreditation expires (Env-C 303.22).
Initial calibration
What auditors check in your initial calibrations.
New Hampshire accredits to the 2016 TNI Standard, and its rule adds a calibration section of its own. Env-C 305.10 points to the TNI instrument calibration requirements and adds a second-source verification step.
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.
Second-source verification before any samples
Env-C 305.10 requires the instrument calibration requirements in Volume 1, Module 2, Section 5.5 of the TNI standards. Before analyzing any samples, every initial calibration must be verified with a standard from a different manufacturer, or from a different lot by the same manufacturer prepared independently from different source materials, backed by manufacturer records.
Source: Env-C 305.10, 2016 TNI Standard
Where the TNI standards and an approved method differ, Env-C 305.10 directs the lab to use the requirements that result in a higher level of confidence in testing results. Document which requirement you followed for each method.
Self-check
Are your initial calibrations ready for a New Hampshire 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.
New Hampshire specifics
A NELAP body with its own calibration section.
NH ELAP accredits to the 2016 TNI Standard and provides primary accreditation to labs inside and outside New Hampshire. Out-of-state labs that already hold accreditation from another primary accreditation body can apply for secondary accreditation, which DES bases on that primary accreditation, limited to matrix, method and analyte combinations NH accredits and to analyte groups identical to its own.
The rule goes beyond adopting TNI on calibration. Env-C 305.10 requires every initial calibration to be verified, before any samples are analyzed, with a standard from a different manufacturer or an independently prepared lot made from different source materials. Where TNI and an approved method differ, the lab must follow whichever gives a higher level of confidence in the results.
The current Env-C 300 took effect November 23, 2021, replacing the version effective January 1, 2017, and the official rule text shows no later amendment as of October 2026. On the drinking water side, DES points to Env-Dw 705.05 and Env-Dw 712.28, which set MCLs and detection limits for four PFAS, and states that labs used for regulatory analysis of them must be accredited by NH ELAP.
How WLTR helps
Calibration evidence ready for a New Hampshire assessment.
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 an NH ELAP assessor.
See how your own ICAL data looks when every analyte and model is laid out for review.
Questions
New Hampshire accreditation FAQs
Is New Hampshire a NELAP state?
Yes. TNI lists the New Hampshire Department of Environmental Services as a NELAP accreditation body accrediting to the 2016 TNI Environmental Laboratory Sector Standard, as of October 2026.
Which labs must be accredited in New Hampshire?
RSA 485:44 requires accreditation for labs testing public water supply compliance and for environmental analyses for other governmental purposes where accreditation is specified, and DES states that labs used for regulatory PFAS drinking water analysis must be accredited by NH ELAP. Labs can also seek accreditation voluntarily under Env-C 300.
Can an out-of-state lab be accredited in New Hampshire?
Yes. NH ELAP provides primary accreditation to out-of-state labs, and grants secondary accreditation based on the accreditation from a lab’s primary accreditation body, for matrix, method and analyte combinations NH accredits, with analyte groups recognized only if identical (Env-C 303.15).
How long does NH ELAP accreditation last?
One year from the date of initial issuance (Env-C 304.01). Labs must participate in at least 2 PT studies per year, plus at least one successful PT study each year for each drinking water method and analyte they seek accreditation for (Env-C 307.01).
Does New Hampshire have its own initial calibration rule?
Yes. Env-C 305.10 adopts the TNI instrument calibration requirements and requires every initial calibration to be verified with a second-source standard before any samples are analyzed.
Sources
Primary sources for this page.
- NH DES, New Hampshire Environmental Laboratory Accreditation Program (opens in a new tab)
- Env-C 300, NH Environmental Laboratory Accreditation Program rules (NH General Court) (opens in a new tab)
- Env-C 300 (NH DES PDF) (opens in a new tab)
- RSA 485:44, laboratory accreditation (opens in a new tab)
- TNI, NELAP 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 New Hampshire Department of Environmental Services. Spot something out of date? Tell us at admin@wltr.tech.
Before your next assessment
See your New Hampshire 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.