M E M O R A N D U M. NFPA Technical Committee on Wood and Cellulosic Materials Processing

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Bruce Harrell
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National Fire Protection Association 1 Batterymarch Park, Quincy, MA 02169-7471 Phone: 617-770-3000 Fax: 617-770-0700 www.nfpa.

1 National Fire Protection Association 1 Batterymarch Park, Quincy, MA Phone: Fax: M E M O R A N D U M TO: FROM: NFPA Technical Committee on Wood and Cellulosic Materials Processing Joanne Goyette, Administrator, Technical Projects DATE: November 7, 2014 SUBJECT: NFPA 664 First Draft TC FINAL Ballot Results (A2016) According to the final ballot results, all ballot items received the necessary affirmative votes to pass ballot. 25 Members Eligible to Vote 5 Not Returned (S. Francis, J. Lysy, A. Mattos, Jr., B. Noe, and D. VanderHyde, Jr.) 14 Members Voting Affirmative (10 with Comment on one or more First Revisions: B. Chastain, J. Cholin, A.Dastidar, D. Guaricci, P. Levitt, K. Mayeaux, B. McLelland, T. Myers, F. Tanguay, and E. Ural) 6 Members Voting Negative on one or more First Revisions (B. Chastain, J. Cholin, K. Mayeaux, T. Myers, F. Tanguay, and E. Ural) 0 Members Voting to Abstain on one or more First Revisions The attached report shows the number of affirmative, negative, and abstaining votes as well as the explanation of the vote for each first revision. There are two criteria necessary for each first revision to pass ballot: (1) simple majority and (2) affirmative 2 /3 vote. The mock examples below show how the calculations are determined. (1) Example for Simple Majority: Assuming there are 20 vote eligible committee members, 11 affirmative votes are required to pass ballot. (Sample calculation: 20 members eligible to vote 2 = = 11) (2) Example for Affirmative 2 /3: Assuming there are 20 vote eligible committee members and 1 member did not return their ballot and 2 members abstained, the number of affirmative votes required would be 12. (Sample calculation: 20 members eligble to vote 1 not returned 2 abstentions = 17 x 0.66 = = 12 ) As always please feel free to contact me if you have any questions.

2 Results by Revision NFPA 664 CMD WOO (A2016) First Draft Ballot Final Results November 7, 2014 FR 62, Global Input, See FR 62 FR 65, Global Input, See FR 65 FR 1, Sections 1.1.1, 1.1.2, See FR 1 Affirmative 17 Affirmative with Comment 2 Peter Levitt An AHJ could interpret that the standard only applies to product woodworking shops and not maintenance or school shops. I believe we do want all dust collectors greater than 1500 cfm outdoors, with explosion vents, etc. I suggest "but not limited to" should be deleted. "production type" should be replaced by "other types of". An appendix item should be added to clarify that the other types of shops include, but are not limited to maintenance and school instructional wood shops. Ken J. Mayeaux Negative 1 Erdem A. Ural Basically agree with P. Levitt. Replace "production type" with "other types of," and add clarification in the appendix. Section worries me deeply. One can have an operation in < 5000 ft2 area and dust collection (system air) flow rate < 1500 cfm and have a severe explosion hazard. A much more important factor, dust generation rate, is completely ignored in this exception. Another change in this section, not addressed in committee statement, is to bring these excepted operations into the standard but not letting important chapters apply to them. Normally, we would rely on 652 to catch the problems. However, the way FR 1 is worded, along with the latest scope statement in 652, will prevent owner/operator or AHJ from identifying and addressing dangerous conditions in the workplace. FR 2, New Section after 1.4.3, See FR 2 Affirmative 17

3 Erdem A. Ural Negative 2 Timothy J. Myers Francois Tanguay This section is not clear. Add the committee statement as annex material. This language is not clear and needs further revision or explanation in an annex. Does the standard retroactively apply to all existing areas and process of the facility OR only to the process changes? Ex: The MEC criteria for pneumatic conveying changed from 75% to 25% (2007 edition to 2012 edition). Existing systems that are operating at 60% of the MEC are now deemed to have a deflagration hazard. If that process doesn't change but another one inside the mill does, it would still affect it? FR 3, Chapter 2, See FR 3 FR 35, New Section after , See FR 35 Affirmative 18 Dan A. Guaricci Distance needs to be defined? Negative 1 Francois Tanguay Safe location as defined is not all inclusive of all the articles where it is currently being used. Article uses 'safe location' with the intent of a safe area outside the building. FR 28, Section No , See FR 28 Affirmative 15 Affirmative with Comment 3 Timothy J. Myers As written this is unclear. Is all wood that is less than 5 mm and 25% moisture content deflagrable, even if testing demonstrates otherwise? Or can testing be used to show that specific material less than 5 mm and 25% moisture content is not deflagrable? Ashok Ghose Dastidar Erdem A. Ural Comments: 1/20" is not 5mm. This is a mathematical error. it should be ~1/5" The text should not read"5 mm (1/20) or smaller". It would be beneficial to say "5 mm (1/5 in.) or smaller. Material passing through a No.4 Taylor mesh screen" Commercial 5 mm screens are not available. the closest is a No.4 Taylor mesh screen which is 4.76 mm. This definition is confusing. The first part ending with "regardless of particle size or shape" is good. The rest may belong to Annex with additional explanation. Didn't we delete ? It contradicts Negative 2 Francois Tanguay In recent years, the criteria for combustible dust has jumped from 420 microns to 500 microns to 5000 microns (5mm), 10x bigger in size. Additional clarification is needed. Also, there doesn't seems to be consistency, as FR 8 (section ) is revised using 500 microns as the criteria to define protection requirements for dust conveying.

4 Ken J. Mayeaux The fairly recent dust testing that was presented during the 2014 TC meeting in Chicago was basis for this change. At that meeting, a subcommittee was developed to further review the various parameters associated with those tests. Perhaps additional testing can (should) be done to further refine the definition. I suggest we hold off on accepting the definition until we hear back from the subcommittee. FR 29, New Section after 4.1, See FR 29 Affirmative 18 Affirmative with Comment 2 Dan A. Guaricci Why have an industry standard if you refer to a general standard. With this statement both apply everywhere. a user has to now read both. Confusing for the user. Francois Tanguay The requirement to comply with NFPA 652 should not be in this standard. If specific articles of 664 refer to 652, then there is a clear path of which requirement are to be complied with. Suggest to remove those last few words: 'and NFPA 652'. FR 30, New Section after 4.1, See FR 30 FR 14, Section No , See FR 14 Affirmative 16 Negative 4 Francois Tanguay That article isn't clear for the user. Why not refer to article of NFPA 654 edition The way NFPA 654 defines how to determine both Dust Explosion Hazard and Dust Flash Fire Hazard is much clearer. So either refer to NFPA 654 or copy it into 664. Ken J. Mayeaux I believe the 5% area limitation was incorporated from the appendix of the which was also later incorporated into the body of 654 where it remains. The validity of the 5% area has been a question for some time and has been a rule of thumb used. However, I agree with J. Cholin, it should be validated and perhaps it's time for a research project. Relocating it to the appendix would seem to be appropriate, but it would also not be consistent with 654 and perhaps even 652. Erdem A. Ural Delete the expression "upward facing." Move this section after the bulk density correction section. Replace 1/8" with the term "allowable thickness" Delete section as it is redundant with section

5 John M. Cholin The 5% area limitation was brought from the annex, where it was advisory, to the body where it is mandatory in the last revision cycle with absolutely no loss data or research to support the need to or legitimacy of this limitation. the area limitation should be returned to the annex unless and until loss history of validated research can substantiate the need for this to be mandatory text. Secondly, the proposed language for seems self evident. the reference to Section 4.3 and 652 should be in the annex. FR 31, Section No , See FR 31 Negative 1 Erdem A. Ural Make the bulk density correction mandatory for all bulk densities. 1/8" thick layer of denser layers present a greater hazard, which is currently ignored by 664. FR 33, Section No , See FR 33 FR 32, New Section after 6.3, See FR 32 FR 11, New Section after 6.3.2, See FR 11 FR 34, Section No , See FR 34

6 FR 36, Section No. 7.1, See FR 36 FR 16, Section No , See FR 16 Affirmative 17 Negative 3 Erdem A. Ural replace "wood" with "wood and wood dust layers" Change temperature criteria to 165 C (329 F), to account for material that dehydrates or carbonizes. Francois Tanguay OSB Press are heated process equipment which are in contact with wood and are exceeding 356oF. That article as written would prohibit the use of those equipment. Many mills will have to shutdown. Ken J. Mayeaux Agree with F. Tanguay regarding OSB presses. Should add a subsection that states high temperatures are acceptable for processes protected in accordance with Chapters 8 and 9. FR 37, Section No , See FR 37 Affirmative 18 Negative 2 Erdem A. Ural Change temperature criteria to 165 C (329 F), to account for material that dehydrates or carbonizes. Francois Tanguay Some furnaces installed in Southern climate would have an outside metal temperature above 356oF even when properly insulated, as that metal temperature is depending on the ambient conditions. FR 17, Section No , See FR 17

7 FR 38, Section No , See FR 38 FR 60, Section No , See FR 60 Erdem A. Ural A GENERAL COMMENT ON CHAPTER 8 Chapter 8 lacks deflagration isolation requirements for ducts and interconnected equipment per NFPA 69. This is a dangerous deficiency that must be fixed. FR 19, Section No , See FR 19 FR 18, Section No , See FR 18 Dan A. Guaricci FR 39, Section No , See FR 39 During operation so called green material areas have had fires and events where material does not clear the process and dry's out. "In green material areas good housekeeping shall prevent material from drying out and being retained by the process." A study is going on in Europe on this very subject.

8 FR 40, Section No , See FR 40 Erdem A. Ural Must add deflagration isolation requirements per 69. FR 41, Section No , See FR 41 FR 20, Section No (A), See FR 20 FR 6, Sections , , , , See FR 6 Affirmative 16 Affirmative with Comment 4 Dan A. Guaricci NFPA 68 does cover venting between vessels if the duct is over 12". Plus the venting of ducts is hard inside considering the need for a vent ducts. Suggest this section be removed. 3 Metal ducts shall be located indoors and shall be equipped with adequate deflagration relief vents that have relief pipes, not exceeding 6 m (20 ft) in length, extending to safe areas outside the building and that have a design strength exceeding the maximum reduced deflagration pressure.and vent ducts designed, installed, and maintained in accordance with NFPA 68 and shall have a design strength exceeding the maximum reduced deflagration pressure. Bruce McLelland Sections , subsections (2),(3),(4) and (5) are confusing and in some cases incorrect. the sections should be rewritten.

9 Francois Tanguay John M. Cholin I agree with Mr. Cholin comments about the rewriting of sub section (2): '... that limits deflagration pressure within the duct to the limits established in NFPA 69'. Sub Section (2) should be reconsidered and edited. A deflagration suppression system cannot have a "design strength exc3eeding the maximum reduced deflagration pressure". It should read "...that limits the deflagration pressure within the duct to the limits established in NFPA 69." FR 42, Section No , See FR 42 FR 8, Section No , See FR 8 FR 21, New Section after , See FR 21 FR 43, Section No , See FR 43 FR 44, Section No , See FR 44

10 FR 22, Section No , See FR 22 FR 25, Section No , See FR 25 Affirmative 18 Affirmative with Comment 2 Peter Levitt If we are going to allow a 5000 cfm & less outdoor cyclone & indoor enclosureless dust collector without the requirement of a a spark detection & extinguishing or abort gate, we should state that, so it is clear to AHJ's. Bruce McLelland Clarification needs to be made that isolation provisions are still required to protect from flame and pressure propagation from the cyclone to the inside enclosureless AMS. Add the following sentence. "When a deflagration hazard exists in the cyclone, isolation provisions shall be made to prevent deflagration flame and pressure propagation from the cyclone back into the building and to the enclosureless dust collector. FR 45, Section No , See FR 45 FR 46, Section No , See FR 46 Bruce McLelland add clarification to the provision. "...meeting the design and application provisions of NFPA 68." With the information presented, it implies the designer is not obligated to any other provisions. The reader should be notified that the vent design criteria can not overlook the performance and application requirements of NFPA 68.

11 FR 23, Section No , See FR 23 FR 24, Section No , See FR 24 FR 61, Section No [Excluding any Sub Sections], See FR 61 Negative 1 Francois Tanguay Removing will make section 8.3 unclear, as it is not written in the same manner as chapters 6 or 7. Section is the equivalent to a performance based design and section contains the prescriptive requirements. Without article the reader won't understand what is required. FR 47, Section No , See FR 47 FR 48, Section No , See FR 48

12 FR 49, Section No , See FR 49 FR 50, Section No , See FR 50 FR 51, Section No , See FR 51 FR 52, Section No , See FR 52 FR 53, Section No , See FR 53

13 FR 54, Section No , See FR 54 FR 55, Section No , See FR 55 FR 56, Section No , See FR 56 FR 57, Section No , See FR 57 Affirmative 17 Francois Tanguay Change 'handling' for 'storing' so it is inline with the intent of which relates to dry fines storage. So it would read like this: 'Any areas storing dry wood particulate shall...'. Also, the word 'detached' has been added to I believe the intent of that article was only to differentiate between 'green' and 'dry' particulate storage, within the same type or area. So should be rewriting like this: 'Any areas that store only green wood particulate shall be permitted to have electrical equipment suitable for Class II Division 2 in accordance with article 500 of NFPA 70'. Negative 2 Brice Chastain Ken J. Mayeaux This requirement should be revised to: Any areas storing dry wood waste particulate shall have Class II, Division 1 electrical equipment. "Storing" should be used instead of "handling" in the requirement. Handling is a broad term; storage is a limiting term and is appropriate in this requirement. Note: All other areas "handling" combustible dusts shall be classified in accordance with Article 500 of NFPA 70. Electrical classification of all combustible dusts is required by regulation to be classified under NFPA 70 Article 500. Agree with B. Chastain. Electrical classification of areas handling dry wood particulate should be evaluated individually in accordance with Article 500 of NFPA 70. FR 58, Section No , See FR 58

14 FR 59, New Section after 10.1, See FR 59 FR 12, Section No , See FR 12 Brice Chastain This requirement should include "flash fire" FR 15, Section No. A.4.3, See FR 15 Brice Chastain The example in the second sentence should be revised to include "flash fire hazards". Suggest the example sentence be revised to: For example in a woodworking facility it would include where fire hazards exist, where flash fires exist, where explosion hazards exist, and what protective measures are in place to protect the personnel and property from those hazards. FR 27, Section No. A (2), See FR 27

15 FR 26, Section No. A , See FR 26 FR 63, Section No. A , See FR 63 FR 10, Section No. A , See FR 10 FR 66, Chapter B, See FR 66 Dan A. Guaricci B1 Add Statement to indicate one or more of the methods might be required. B.4.1 Add Flame less vent as an option. B 6 Section limits applicability to ducts of less then 1' or requires an isolation method to be used. Suggest eliminating this statement. "Although NFPA 68, Standard on Explosion Protection by Deflagration Venting, indicates venting as an option for interconnections, venting is valid only when interconnected equipment is protected from explosions." B.6.1 Mechanical Isolation. Should be expanded to include the many Passive Mechanical Isolation Devices available. The only once listed are the higher cost quick sliding valve or chemical isolation. Lower cost isolation methods are available. FR 67, Chapter C, See FR 67 Affirmative 18 Affirmative with Comment 2

16 Dan A. Guaricci The examples indicate the use of an explosion vent. This considers the hazard to require and explosion isolation system if the air is returned to the building. If venting is shown with a spark detection and extinguishing system then isolation should also be shown. This is a common misconception with users as they apply an abort gate and think it protects against the deflagrations propagation. While they can the construction of most won't stop a deflagrations pressure. It must be clear that Spark systems are a great first step to prevent explosions explosion protection is not provided by them. Peter Levitt In illustrations C & C.2.2 the spark detectors are located after the dust collector. Is this the required/preferred location for the detectors? I thought they should be located before the dust collector. FR 68, Chapter D, See FR 68 Dan A. Guaricci Figure D.1 Figure indicates a cyclone and dust collector both having a deflagration hazard. But the isolation between the two only shows isolation required from the DC to the cyclone considering the device shown is a single direct device. Since the cyclone has isolation on the inlet it should have it on the outlet. Venting of duct work shown between DC and Cyclone only applicable per NFPA 68 if duct size is under 12+" and shorter then 20' which does not fit most process ducts. FR 69, Chapter E, See FR 69 FR 13, Chapter F, See FR 13

National Fire Protection Association. 1 Batterymarch Park, Quincy, MA Phone: Fax:

National Fire Protection Association 1 Batterymarch Park, Quincy, MA 02169-7471 Phone: 617-770-3000 Fax: 617-770-0700 www.nfpa.org MEMORANDUM TO: FROM: Correlating Committee on Combustible Dusts Susan