Tom Johnson, a frequent contributor to our newsletter posted the following message on the NAFEM localregs listserv on October 11, 2005. UP YOUR STACK® includes his message explaining reasoning for the requested change to NFPA 96. A TIA or Tentative Interim Amendment has been currently posted in the October, 2005 NFPA NEWS. Public comment is required by December 7, 2005.
Author: Tom Johnson
It is very important that NFPA 96 hears form industry on the proposed TIA.
NFPA has responded to my request for a TIA in the October NFPA News letter and is asking for public comment. It is found on page one and two at the following link: http://www.nfpa.org/assets/files/PDF/NFPA%20News/nfpanews1005.pdf
Recirculating hood systems listed to UL710B, such as the Giles, Wells Mfg, Autofry and others are presently NOT required to have secondary exhaust ventilation. The rationale is that the recirculating system cleans up the discharge air to the extent that it no longer has smoke and grease vapor in it to levels that could present a fire hazard in the space.
Note; recirculating systems were formerly referenced in UL197 SB (supplemental bulletin). UL197 is the standard for cooking equipment and UL felt that it was more appropriate to place such criteria in test methods for commercial exhaust hoods, thus, the criteria was moved from UL197 to UL710. UL710B is the section of the referenced standard that relates to recirculating or other systems designed to reduce particulate emissions from thermal food processes.
If processes that rely on secondary recirculating filter systems to reduce emissions can be installed without a hood, then processes that are tested to be below the same thresholds WITHOUT needing a secondary system to filter the discharge air should not need a hood. This is the heart of the request to modify NFPA with a TIA.
Note that recirculating systems do not totally remove all contaminants from the discharge air, but rather they reduce emissions form the process to a point that it is considered safe to discharge without exhaust ventilation.
The test method used to verify emission rates for cooking processes is found in UL710B under several subcategories, and it makes reference to EPA 202, the test for condensable particulates. One subcategory is for systems tested together (e.g. specific model fryer/recirculating hood), and another (KNLZ) is for integral grease/smoke limiting devices, such as the catalytic system in Turbo Chef’s equipment.
There are many in the NFPA community that doubt that franchisors will exert the type of control over the evolution of their in-store processes to the extent that they would or could limit their franchisee’s to tested processes ONLY.
The crux of the issue is the managerial control discipline of the franchisor (or independent operator for that matter) exercised to assure that if and when a franchisee changes or expands their thermal food processes, that the system will be re-evaluated and if necessary, brought into compliance with the more stringent criteria. For independents, the matter is further complicated unless some kind of agreement can be reached (and remembered) by the AHJ and the operator.
There may be a need to suggest modification to model mechanical codes to the extent that AHJ’s can enter into agreements with operators about frames of intended use and when their plans and operations change, the operator agrees to first resubmit to the AHJ to assure the revised processes are still adequately protected.
Please be sure to write a comment to NFPA supporting the concept that when tested processes are below the reasonable threshold for smoke and grease vapor, that systems be allowed to be installed without secondary exhaust ventilation systems.
Please fell free to post any questions or concerns you may have about this on the NAFEM localregs listserv.
Thank you
Thomas Johnson, President
Johnson Diversified Products, Inc.
1408 Northland Dr #407
Mendota heights, MN 55120
W 800-676-8488x101
F 651-686-7670
C 651-587-0418
http://www.jdpinc.com |
