Skip to Content
Questions or Comments:

Quality Assurance

Folder Owner: Office of Compliance and Enforcement

Environmental Laboratory (NELAP) Accreditation

This page offers information on the Agency's National Environmental Laboratory Accreditation Program (NELAP)

Effective January 31, 2020, laboratories are assessed against the provisions of the 2016 TNI NELAP standard.

Please see link for summary of changes below.

Changes to the various standards used in the National Environmental Laboratory Accreditation Program (NELAP) (PDF)


COVID-19 Response procedures

UPDATE 2 (replaces Update 1.1):

Laboratory accreditation staff have switched to a hybrid work schedule with the bulk of the time spent working remotely.  Therefore, to ensure submitted documents are available for processing as expeditiously as possible, we are requesting laboratories continue to adhere to the following until further notice:

1.  Submit all laboratory accreditation payments to TCEQ revenue section at the following address.  Do not submit them directly to the TCEQ Laboratory Accreditation Program.

Texas Commission on Environmental Quality
Cashier's Cage
P.O. Box 13088, MC-214
Austin, TX 78711-3088

Their physical address for overnight/non-US mail deliveries is:

Texas Commission on Environmental Quality
Cashier's Cage
12100 Park 35 Circle
Austin, TX 78757

2.  Submit all laboratory accreditation-related documents electronically.  There is no need to follow up with hard copies.

3.  If you do not know the e-mail address of the individual recipient, please use the mailbox, which is being monitored in real time during regular office hours. 

4.  Laboratory accreditation staff will not have immediate access to their phones.  They will be checking their messages periodically; however, there may be a delay in a response.  If possible, send an email message in conjunction with the voice message as staff have immediate access to their emails.  In addition, staff will be monitoring and responding to email messages sent to

5.  Laboratories will receive electronic copies of their certificates and scopes.  Hard copies will not be mailed.

If you have any questions about these directives, please contact TCEQ Laboratory Accreditation Program (TCEQ LAP) at

TCEQ LAP encourages laboratories to ensure the safety of their employees and understands there may be some disruptions to normal operations.  Any laboratories that are closing due to COVID-19 need to notify TCEQ LAP as soon as possible.  In addition, TCEQ will evaluate situations where a laboratory is unable to fulfill any requirements in the standard due to disruptions from COVID-19 on a case-by-case basis.

TCEQ will be providing updates on our web page and through our laboratory GovDelivery email notification system as the situation changes.

Subscribe to Laboratory Accreditation Program e-mail updates

Go to this link: Get email or text updates on your choice of topics.

After entering your email address or phone number, select “Environmental Laboratory Accreditation” from the list. You can unsubscribe any time.

Back to top

Application, Fields of Accreditation, Checklists, and Procedures

Application (PDF) (Revision 10 - February 2020)

Fields of Accreditation (FoAs) (PDF) (Revision 18 - April 2019)

Technical Manager Qualification Form (PDF) (Revision 1, fillable - October 2023)

History of changes to the Fields of Accreditation (PDF)

The current list of accredited laboratories, with links to their scope of accreditation, can be accessed here:

List of Accredited Laboratories (Word)

The accreditation team uses the 2016 TNI Quality Systems checklist to determine each laboratory's conformance to the elements of this Standard. A copy of the TNI checklist is now available directly from their web page.

Be advised that you must have a copy of the TNI Standard ELV1, Management and Technical Requirements for Laboratories Performing Environmental Analyses (2016) before you may download this checklist.

TCEQ (Internal) Accreditation Procedures (PDF)

Accreditation applications in progress (Word)

For administrative information, please contact our records specialist at

For additional information, including suitable ways to obtain traceability of measurements, or to make a complaint, please contact the program manager at

Back to top

Laboratory Resources

FAQ guides. This is a document addressing frequently asked questions regarding the Texas laboratory accreditation program:

FAQ guides (PDF)

Corrective Action Response (CAR) form.

CAR form (Excel) (Revision 4 - October 2023)

CAR form instructions (PDF) 

Corrective Action Response Guidelines For TCEQ Accredited Laboratories (Presentation from 2017 Trade Fair) (PowerPoint)

MUR information

Back to top

External Links

The NELAC Institute (TNI)

National Environmental Laboratory Accreditation Program (NELAP) designated proficiency testing providers

NELAP Fields of Proficiency Testing

Link to the EPA Methods Update Rules web page

Back to top

Our mailing address is:

Texas Laboratory Accreditation Program
Texas Commission on Environmental Quality
P.O. Box 13087, MC-165
Austin, TX 78711-3087

Our physical address for overnight mail delivery is:

Texas Laboratory Accreditation Program
Texas Commission on Environmental Quality
12100 Park 35 Circle, Bldg B, MC-165
Austin, TX 78753

Back to top

Rules (Including Fees) and Accreditation Standards

Title 30, Texas Administrative Code, Chapter 25 , Subchapters A and B (for a schedule of fees refer to §25.30)

Back to top

Quality Assurance

The goal of the Quality Assurance team is to help ensure that the environmental data generated and collected by or for TCEQ is of known quality. The quality of the data becomes known through thoroughly documenting processes and ensuring that those processes are followed.

The following sections provide information about the various quality assurance documents and processes:

TCEQ Quality Assurance Team Key Contacts

  • D. Jody Koehler (512) 239-1990
    TCEQ QA Manager

Quality Management Plan

The Quality Management Plan (QMP) documents and describes the organizational arrangements, processes, procedures, and requirements of TCEQ’s Quality Assurance (QA) program. Approval of the QMP by TCEQ senior management reflects the agency’s commitment to the principles and quality system defined in the document.

The QMP contains 18 sections organized to parallel federal guidelines and national standards

  • Title, Table of Contents, and List of Acronyms and Abbreviations
  • QMP Approvals
  • Quality Statement
  • Organization Charts
  • Roles, Responsibilities, and Authorities
  • Technical Activities and Programs Supported by the QMP
  • Conformance with Policies, Procedures, Standards, and Regulations
  • QA Field Activities
  • Computer Hardware and Software
  • Information Quality Guidelines
  • Organization Competence
  • Personnel Training
  • Procurement of Items and Services
  • Document and Record Processes
  • Plan Do Check Act (PDCA) Model
  • Dispute Resolution Process
  • Continual Improvement
  • Data Review, Validation and Verification, and Data Usability Reporting

The current version of the TCEQ QMP  is available electronically for download

EPA Quality Assurance Requirement and Guidance Documents

EPA has developed a number of documents which contain requirements and guidance to assist in the development and implementation of quality systems for both EPA and non-EPA organizations.

Corrective Action Process

The corrective action process is a tool to identify and fix deficiencies in a system that, if not corrected, may have a negative impact on project deliverables.

Identification of Quality System Deficiencies

  • A deficiency is defined as any unauthorized deviation from acceptable procedures or practices, a defect in an item, or failure to conform with a specified requirement.
  • Deficiencies may be identified during the course of a formal agency audit or internal audit. Deficiencies may also be self-identified during the course of routine work.
  • Deficiencies shall be documented immediately and reported to supervisory personnel in writing. The reports of deficiencies to supervisory personnel will serve as initial deficiency notices.
  • Supervisory personnel shall forward initial deficiency notices to the appropriate Project Manager and lead QA staff. Lead QA staff shall determine whether or not deficiencies are significant conditions as defined in the TCEQ QMP, including cases in which deficiencies recur after having been identified and previously corrected. Project, program, and organizational managers may also determine whether deficiencies are significant conditions.
  • Lead QA staff shall notify affected Deputy Directors, Section Managers, Grant and Program Managers, and the QA Manager of any significant conditions.
  • If lead QA staff and project, program, or organizational management disagree as to the determination of significant conditions for a deficiency, any of the parties may appeal to the TCEQ QA Manager for resolution.

Planning and Implementing Corrective Actions

  • With concurrence of affected lead QA staff, Project Managers or designees shall prepare a corrective action plan (CAP) to determine and document the following with regard to each deficiency:
    • root cause(s);
    • programmatic impacts;
    • required corrective action(s);
    • required corrective action(s) to prevent recurrence;
    • means by which corrective actions will be verified as effective;
    • means by which corrective action completion will be documented;
    • timetable(s); and
    • individual(s) responsible.
  • Within 30 days of the initial deficiency notice, the project manager or designees shall submit forward copies of CAPs to supervisory and lead QA staff involved in implementing or monitoring corrective actions. Lead QA staff shall forward copies of CAPs concerning significant conditions to the affected Deputy Directors, Section Managers, Grant and Program Managers, and the QA Manager.
  • Supervisory staff shall ensure CAPs are implemented effectively and in a timely manner. Lead QA staff may monitor the implementation of CAPs and shall advise the appropriate project and program manager if the plans are not implemented in a timely manner. In the case of significant conditions, the lead QA staff shall advise the appropriate Deputy Director, Section Manager, and the QA Manager if CAPs are not implemented in a timely manner.
  • Depending upon program requirements, either the Project Manager or QA staff will notify affected management and the lead QA staff when corrective actions have been completed and verified to be effective, and that the associated CAP(s) can be closed. In the case of significant conditions, the lead QA staff shall advise the Project Manager, Program Manager, and appropriate Deputy Director, Section Manager, and QA Manager when corrective actions have been completed and verified to be effective, and that the associated CAP(s) can be closed.
  • The current version of the TCEQ QA CAP template (Word) is available for download.
  • For resources specific to TCEQ's National Environmental Laboratory Accreditation Program (NELAP), please visit the TCEQ Environmental Laboratory Accreditation webpage.

Quality Assurance Project Plan

A Quality Assurance Project Plan, or QAPP, is a formal document that describes in comprehensive detail the necessary quality assurance, quality control, and other technical activities that must be implemented to ensure that the results of the work performed will satisfy the stated performance criteria.

Drafting a New QAPP

  • QAPPs shall be drafted, with the assistance and involvement of all relevant Program and QA staff, to meet the requirements contained in CIO 2105-S-02.0 . QAPP templates, also known as “shells”, are available for certain programs. The TCEQ Project Manager can provide more information on QAPP shells.
  • All participating organizations are given 30 days to review the initial draft and provide comment.
  • To avoid delays in project initiation, the QAPP should be submitted to TCEQ Project Managers at least four months before the planned start date (especially for QAPPs requiring EPA approval) unless other arrangements have been made.
  • No work covered under the QAPP shall begin until the QAPP has been fully approved with signatures affixed.

Amending a QAPP

  • Amendments to QAPPs are developed and approved to reflect changes in project organization, tasks, schedules, objectives, and/or methods; address deficiencies; improve operational efficiency; and accommodate unique or unanticipated circumstances. These changes will remain in effect until the next revision of the QAPP.
  • Amendments are effective immediately upon approval by the TCEQ Project Manager or designees, the Lead QA Specialist, the TCEQ QA Manager (or designee), and the EPA Region 6 Project Officer (when required). Amendments to QAPPs and the reasons for the changes shall be documented by the TCEQ Project Manager and distributed immediately to all individuals and organizations contained in the QAPP distribution list.
  • Amendments shall be incorporated into a revised QAPP during the anniversary revision process, or within 120 days of the QAPP's approval in cases of significant changes. For multi-year QAPPs, amendments must be attached to and noted in annual certification submissions.

Annual Certification of a Multi-Year QAPP

  • Multi-year QAPPs for EPA-funded programs and projects must be reviewed annually by the appropriate TCEQ Project Managers or Lead QA Specialist.
  • Reviews must be documented and include the relevant signatures to certify the review’s accuracy as well as copies of any program or project changes which were approved via amendment during the prior year.
  • If the annual certification process reveals the need for amendments to be made to the project, these should be approved by the EPA (or TCEQ QA Manager for delegated programs) before the completion of the annual certification.
  • Any minor administrative changes that will not have an impact on data or operations (e.g., organizational changes, schedule changes not affecting the project design or quality or quantity of work to be performed, etc.) shall also be included as part of the annual certification.
  • TCEQ Project Managers or designees must provide certification of the annual reviews to the TCEQ QA Manager and the appropriate EPA Region 6 Project Officer 30 days before the annual anniversary date.

QAPP Revisions and Reissuances

  • Until the work outlined in the QAPP is completed, the QAPP shall be revised as necessary and reissued by its expiration date or revised and reissued within 120 days of significant changes, whichever is sooner.
  • If the entire QAPP is current, valid, and accurately reflects the project goals and the organization's policy, the reissuance may be done by a certification that states that the plan is current and includes a copy of new, signed approval pages.

QAPP Approval Timetable

  • Unless other arrangements have been approved, new QAPPs, including annual and multi-year QAPP updates, shall be prepared and approved according to the following timetable.
Activity Office/Organization Timetable
Submittal for TCEQ QA review 135 days before project initiation/ QAPP expiration date
TCEQ Approval/Submittal to EPA 75-90 days before project initiation QAPP expiration date
Comments/ Approval from EPA 15 days before project initiation/ QAPP expiration date

For additional information regarding the preparation, review, approval, and distribution of QAPPs, please reference Appendix F of the TCEQ QMP

Method Update Rule (MUR) for Laboratories

Revisions to lab methods for non-potable water and drinking water, adding to fields of accreditation (FoAs) for proficiency testing, and how these apply to your lab’s accreditation.

In 2019, the TCEQ Laboratory Accreditation Program revised its fields of accreditation (FoAs) to include the following analytical methods:

  • Non-Potable Water: EPA 608.3, EPA 624.1, and EPA 625.1
  • Drinking Water: SM 4500-Cl¯ B, and ASTM D516-11

This revision incorporates methods from the most recent Method Update Rule (MUR) and adds methods that the TCEQ Drinking Water Program requested. Find the additional methods and analytes in Appendix A: Analytes and Methods for Water Quality Testing Adobe Acrobat PDF Document.

Applying to Add to Your Labs’ Accreditation

To add any of the additional parameters listed in Appendix A (above) to an existing scope of accreditation for your lab, submit the following, depending on whether your lab is accredited as a Primary Lab or Secondary:

Primary Labs

  • An amended application
  • Applicable FoA sheets
  • A $250.00 administrative fee
  • Associated documentation including:
    • Standard operating procedures
    • Demonstrations of capability and method detection limit studies
    • Applicable proficiency testing (PTs) results for all parameters being added [that are also fields of proficiency testing (FoPTs)]

Secondary Labs

  • An amended application
  • Applicable FoA sheets
  • A $250.00 administrative fee

Note: Your laboratory will not have to pay the $250 administrative fee to change the scope of accreditation if it is done as part of the laboratory’s annual renewal. Any applicable category fees will still apply. If your laboratory has submitted PT results for EPA Methods 608, 624, and 625, you are not required to submit PT results for EPA Methods 608.3, 624.1 and 625.1.

TCEQ will review applications in the order they are received. Laboratories submitting incomplete or inaccurate applications will be notified of the deficiencies and will need to submit a corrected application. Corrected applications will be placed in the queue based on the date received.

For application forms and where to send them, see our NELAP Accreditation webpage.

Need More Information?

For questions about what data will be accepted, contact the TCEQ Water Quality Division at 512-239-4539 or

For questions about the two new Drinking Water methods, contact the quality assurance officer for the Water Supply Division at 512-239-4691 or

For more information about the EPA methods see the EPA Methods Update Rules