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Adjudicating GRaDER Retest Requirements

During the course of conformity assessment testing, some systems may not satisfy the criteria in the Compliance Levels for GRaDER Instrument Performance or the requirements outlined in the applicable standards. In such cases, the instrument manufacturer may choose to take corrective action and ask the Domestic Nuclear Detection Office (DNDO) to evaluate the improved instrument or revised operating procedures.

Learn more below about DNDO's process for determining which subtests and standard clauses may be retested for DNDO to reevaluate the instrument. The process involves the manufacturer throughout, and results in guidance that the test laboratory will use to develop a new test plan. Each non-conformity is evaluated on a case-by-case basis.

When is re-testing required?

  • Upon expiration of the original listing on the Graduated Rad/Nuc Detector Evaluation and Reporting (GRaDERSM) Evaluated Equipment List (GEEL), which is 4 years after original test, resulting in a change to Compliance Level (CL) 0
  • Following a non-cosmetic configuration change, to either hardware or software in the current model (cut-in date and serial number are required)
  • When a discontinued model is replaced by later model (new start); the old model will be assigned CL 0 at 4 years after the original test
  • Failed Government Post-market Surveillance (GPMS) resulting in change to CL 0
  • After a failure to complete original scope of conformity assessment testing, resulting in CL 0

When can re-testing be done voluntarily?

  • The manufacturer may wish to re-test shortfalls that originally prevented the instrument from demonstrating CL 1 or 2 compliance (CL 0 assigned based on DNDO evaluation).
  • In order to extend the product's duration on the GEEL, the manufacturer may wish to re-test the subtests and/or clauses revised in the new version of the applicable standard, but is not required to do so before the end of the 4-year cycle. DNDO intends to implement new versions of standards within one year of publication.

Who pays for testing?

  • Manufacturers pay for all testing against American National Standard Institute/Institute of Electrical and Electronic Engineers (ANSI/IEEE) N42 standards (Compliance Levels 0, 1 and 2), unless otherwise stipulated by the government.

Who conducts testing?

  • Any DNDO-accepted or National Voluntary Laboratory Accreditation Program (NVLAP)-accredited laboratory with the appropriate scope for testing the desired instrument model can conduct testing. Labs can become DNDO-accepted through a self-declaration of conformity assessment and a DNDO Letter of Acceptance.

How is the scope of re-testing determined?

The scope of re-testing is determined by instrument model, based on:

  • test objectives
  • previous test results and manufacturer's regression test results
  • manufacturer's failure analysis and corrective action plan
  • changes to instrument design, and
  • DNDO analysis and determination.

The resulting testing scope is to be summarized in a test plan generated by the test laboratory, coordinated and agreed to by the manufacturer and DNDO.

When will the GEEL be updated with the new results?

The following must occur:

  1. The testing laboratory will provide DNDO with original test results, with the manufacturer's approval. DNDO will then begin a systems engineering assessment of identified failures, subtests and conditions contributing to the product failures, and identify any issues with test procedures carried out at the testing laboratories. After completion of the assessment, the product may be listed on the GEEL at the appropriate Compliance Level based on published criteria and results of the original test. The GEEL will be updated with evaluations of re-test results once they are completed.
  2. The manufacturer must conduct and submit a failure analysis and proposed mitigation/corrective action measures to support the engineering assessment.
  3. The manufacturer must submit details of all changes made to the instrument in order to support the engineering assessment.
  4. The manufacturer may submit proposed test objectives; for example, they may choose to provide a list of recommended test requirements to be re-tested, and any proposed test modifications.
  5. DNDO will complete a systems engineering assessment using the information submitted by the manufacturer, and then determine the minimum proposed requirements for a system re-test, and will then respond to the manufacturer in writing.
  6. After conferring with the laboratory and the manufacturer, DNDO will determine the minimally-acceptable test requirements for GRaDER evaluation, and any necessary adjustments to the original test plan. The laboratory and manufacturer must then submit the new test plan for consideration. DNDO must concur on/accept the test plan in writing in order for the results to be considered.
  7. The manufacturer will provide test articles, fund the test, and complete contractual agreements with the testing laboratory. GRaDER will not provide funding for a system re-test of Compliance Level 1 / 2 requirements.
  8. The manufacturer will execute a new product listing agreement with DNDO, and provide a new test results release agreement to DNDO and the test laboratory. The manufacturer is allowed to see the results of the tests before submission to DNDO.
  9. The laboratory will complete testing, and provide a test report to DNDO and the manufacturer, per published GRaDER guidance, Interagency Agreement scope of work (if applicable) and the test plan.
  10. DNDO will use published criteria to complete a new evaluation of the instrument and produce a new evaluation summary based on cumulative test results.
  11. DNDO will publish an updated GEEL and submit a new evaluation summary to the Responder Knowledge Base (RKB) and the Homeland Security Information Network (HSIN) for posting.

Decision Dendritic for GRaDER Re-testing

Download the Decision Dendritic for GRaDER Re-testing
(PDF - 1 page, 135 KB)

DNDO will complete an analytic process, as outlined in the Decision Dendritic for GRaDER Re-testing, to determine the minimum testing required to:

  • Resolve issues related to incomplete tests;
  • Address performance shortfalls that prevented instruments from demonstrating Level 1 or Level 2 compliance; and
  • Identify test requirements for GPMS or extension of instrument listing on the GEEL beyond 4 years.

This determination will be accomplished in coordination with the manufacturer and the test laboratory.

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