BUBBLE TIGHT DAMPERS FAQS
Answers to your most Frequently Asked Questions about Greenheck bubble tight dampers.
The short answer is no, however, never give up on this account. Greenheck Industrial Dampers are manufactured under a certified ISO9001 Quality Assurance Program (QAP). This QAP is very stringent, but is not certified to NQA-1 per the DOE and NUPIC criteria. However, Bud Fabian and Yung Liu of Argonne National Laboratory summary in a 2006 paper titled Quality Assurance Standards ISO-9001 and ANSI/ASME NQA-1 – A Brief Comparison states:
The NRC recommends that should an ISO-9001 supplier be used, additional QA requirements must be added to the purchase order to assure compliance with Subpart H. The additional QA requirements should be part of a dedication process for commercial-grade items and activities. The ASME NQA-1-2004 has a comprehensive dedication process. (See Requirement 7, Section 700, and Non-mandatory Appendix 7A-2, for the dedication process. See NRC Generic Letters (GL) 89-02 and 91-05 for the common mistakes made by licensees using the dedication process.)
In summary, items and activities that are not important to (nuclear) safety can, in most cases, be purchased from an ISO-9001 supplier; however, additional QA requirements must be imposed on the ISO-9001 suppliers in the procurement of important-to-safety items and activities for Type B radioactive and fissile material transportation packaging. This is consistent with the approach described in NRC Regulatory Guide 7.10 (Rev. 2) and SECY-03-0117
Keeping in mind that most of your applications are not in nuclear facilities will also allow more leniency on using a quality program outside of the nuclear world, but still adhering to the integrity of the final product.
$$Qavg = {(Pi - Pf) * V \over (Ti Tf) R * Δt * 0.075} $$
If the damper is tested to zero bubble, then 15 minute criteria will always be used and the leakage rate will be zero. Therefore, as a general rule, we don’t test to the pressure decay method as the testing time and set up are longer and the test method doesn’t align with the bubble tight product requirements as it assumes some level of leakage. Pressure Decay testing can be provided at an added cost if the engineer absolutely requires it, contact the factory for pricing.