Louisiana LELAP
Louisiana environmental lab accreditation, LELAP and NELAP.
Which labs must hold LELAP accreditation, how the Louisiana cycle runs, why out-of-state labs need it too, and what auditors look for in your initial calibrations.
At a glance
How environmental lab accreditation works in Louisiana.
The Louisiana Department of Environmental Quality runs LELAP and is one of the NELAP accreditation bodies. Drinking water labs are certified separately by the Louisiana Department of Health.
NELAP accreditation body
- Program
- Louisiana Environmental Laboratory Accreditation Program (LELAP), Louisiana Department of Environmental Quality, Office of Environmental Services
- Legal basis
- La. R.S. 30:2011; Louisiana Administrative Code Title 33, Part I, Subpart 3, Chapters 45 to 59. Chapter 59 covers NELAP accreditation.
- Standard
- NELAP accreditation to the TNI standard. LDEQ’s assessment checklist is built on the 2016 TNI Standard.
- Who needs it
- Commercial labs, wherever they are located, that supply data to LDEQ for a facility, permit application, order or monitoring report. LDEQ cannot accept that data from a non-accredited commercial lab.
- Exempt
- In-house and government labs, labs accredited by the Louisiana Department of Health, and certain radiation personnel monitoring services (LAC 33:I.4501 and the definition of commercial laboratory in LAC 33:I.4503)
- Matrices
- Air emissions, non-potable water, solid and chemical materials, and biological tissue
- Drinking water
- Certified by the Louisiana Department of Health, Bureau of Laboratory Services, under LAC 48:V, Chapter 80. Certificates last one calendar year, with reciprocity available based on a NELAP primary accreditation.
The accreditation cycle
The LELAP accreditation cycle.
The cycle below summarizes the LELAP program page and the Louisiana Administrative Code.
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Apply by test category
Apply for the matrices and test categories your lab reports. LAC 33:I.4705 defines eleven categories, from metals and organics to dioxins, radiochemistry and asbestos.
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Proficiency testing
At least two PT studies per field of accreditation each year, about six months apart, with acceptable results in two of the three most recent studies.
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On-site assessment
At least every two years.
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Renewal
Accreditation runs one year and is renewed annually (LAC 33:I.5703), with test category fees due each year. A renewal application and application fee are due every three years, counted from the fiscal year of the initial application.
Initial calibration
What auditors check in your initial calibrations.
LELAP assessors work from the TNI standard, your methods and Louisiana’s own quality system rules. On calibration, those point to the same questions.
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.
Calibration and traceable standards
Louisiana’s rules require equipment to be calibrated where appropriate, and labs to “verify and document all standards versus primary (reference) standards.”
Source: LAC 33:I.5305
LDEQ has also issued a LELAP memo on implementing EPA’s 2024 Clean Water Act Method Update Rule. If your methods changed version, expect assessors to check that your calibration procedures changed with them.
Self-check
Are your initial calibrations ready for a Louisiana 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.
Louisiana specifics
A NELAP certificate from another state is not enough on its own.
LELAP is built around commercial labs, and it applies to them wherever they are located. A lab in Texas or Florida that sends data to LDEQ for a Louisiana facility needs Louisiana accreditation as well, even if another NELAP body already accredits it.
Secondary accreditation, which LDEQ calls accreditation by recognition, makes that simpler, but it is still a Louisiana accreditation with Louisiana fees. In-house and government labs are exempt from LELAP.
LDEQ posted an updated LELAP interpretations document and a revised test categories list in 2026. Check the program page before your next assessment.
How WLTR helps
Calibration evidence ready for a LELAP 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 a LELAP assessor.
See how your own ICAL data looks when every analyte and model is laid out for review.
Questions
Louisiana accreditation FAQs
Is Louisiana a NELAP state?
Yes. The Louisiana Department of Environmental Quality is a NELAP-recognized accreditation body. The Louisiana Department of Health, which certifies drinking water labs, is not.
Which labs need LELAP accreditation?
Commercial labs, wherever they are located, that supply data to LDEQ for a facility, permit application, order or monitoring report. In-house and government labs are exempt.
Does an out-of-state NELAP lab need LELAP accreditation?
Yes, if it submits data to LDEQ. It can apply for secondary accreditation, which LDEQ calls accreditation by recognition, based on its primary NELAP accreditation.
How often are LELAP labs assessed?
On-site assessments take place at least every two years, PT is required twice a year per field of accreditation, and accreditation is renewed annually, with a full renewal application every three years.
Who certifies drinking water labs in Louisiana?
The Louisiana Department of Health, Bureau of Laboratory Services, under LAC 48:V, Chapter 80. Certificates last one calendar year.
Sources
Primary sources for this page.
- LDEQ, Louisiana Environmental Laboratory Accreditation Program (opens in a new tab)
- LAC 33:I, Subpart 3, Laboratory Accreditation (LDEQ copy) (opens in a new tab)
- Louisiana Department of Health, drinking water laboratory certification (opens in a new tab)
- TNI list of 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 Louisiana Department of Environmental Quality. Spot something out of date? Tell us at admin@wltr.tech.
Before your next assessment
See your Louisiana 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.