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Secretary of Labor Thomas E. Perez
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Web Chat with OSHA - Combustible Dust (Static Version)

Monday, June 28, 1 p.m. EDT

12:47 Moderator: Welcome! Our chat will begin at 1 p.m. EDT but you can enter your comments or questions at any time. This is a text-only chat, so there will be no audio or video. Questions will show up in the main chat window when they are answered.

1:00 OSHA Comb. Dust Team: Welcome to OSHA’s first ever “virtual stakeholder meeting.” If you missed Dr. Michaels’ video message welcoming stakeholders to this Web Chat, please take a moment to listen to it now by clicking on the link on the top of the page, or by going to .

As you know, OSHA is developing a rule to address the hazards of combustible dusts which encompass a wide variety of materials, industries and processes. In this Web Chat, OSHA will pose questions and will be available for clarification of the questions, if necessary. The Web Blog will remain active through July 7, 2010. OSHA will monitor the site, provide additional information and pose follow-up questions when appropriate.

The purpose of this Web Chat is to gather information that will be helpful in developing a new rule for combustible dust. Please limit your responses to the questions being asked, or constructive comments for use in developing the new rule. Please do not post documents to the blog. Questions about open cases or enforcement issues of existing standards are not appropriate in this forum.

Your input will help us develop a protective and feasible rule, in a timely manner. Rulemaking can be a lengthy process, but this is a priority for the Agency and we are progressing as quickly as we can. As Dr. Michaels said, this is an important rulemaking and we appreciate your assistance.

Thank you!

1:01 Comment From Enrique S.: Hello. Will there be a transcript available after the meeting?

1:01 Moderator: The transcript of this chat will remain available at this same web page after the chat is over.

1:02 OSHA Comb. Dust Team: 1. At the previous OSHA combustible dust stakeholder meetings there was considerable discussion about how OSHA should define combustible dust and how that definition could or should be used to determine what types of facilities would be covered under the scope of an OSHA standard. The consensus standards addressing combustible dust use varying definitions for combustible dust. Under its National Emphasis Program (NEP) for combustible dust, OSHA currently treats any dust with a Kst > 0 as combustible. Some stakeholders have objected to this approach, arguing that low Kst dusts should not be treated as combustible.

How should OSHA define combustible dust?
Should OSHA rely on the Kst values? If so, are you aware of any data or information showing that low Kst dusts do not present an explosion, deflagration or flash fire hazard to workers? Alternatively, should low Kst dusts be treated differently, requiring less stringent controls than higher Kst dusts?

Are there other variable cutoffs (e.g., particle size distribution, Pmax, MIE) that OSHA should use in determining whether or how to regulate a dust?

1:02 OSHA Comb. Dust Team: 2. During the stakeholder meetings, there was considerable discussion as to whether OSHA should take a performance versus a specification based approach towards regulating combustible dusts. OSHA is aware that employers want compliance options but is interested in your opinions about how best to provide regulatory flexibility. OSHA is considering a balance of performance based and specification based requirements.

With that in mind, which administrative controls and engineering controls are better addressed by performance-based requirements and which are better addressed by specification-based requirements?

1:02 OSHA Comb. Dust Team: 3. OSHA already has a standard that addresses combustible dust in large portions of grain handling facilities. Several groups participating in OSHA’s combustible dust stakeholder meetings argued that the OSHA’s grain dust standard has been highly successful in reducing combustible dust explosions and recommended that OSHA continue to regulate the grain industry under that standard and not cover grain handling facilities under the scope of a new combustible dust standard. OSHA is concerned however that certain portions of grain handling facilities might not be covered under the grain dust standard.

Are there portions of these types of facilities that are not protected by the current grain dust standard? If so, what are they and what should OSHA do to address those areas?

1:03 OSHA Comb. Dust Team: 4. What kinds of costs and benefits do you foresee from a proposed rule? What alternatives should OSHA consider that could minimize costs without sacrificing safety? How will a possible rule affect existing businesses? How will it affect new businesses trying to start up? How can impacts (especially for small businesses) be minimized without sacrificing safety?

1:04 Comment From Brad Meushaw: Please keep in mind that although the standard will be used by engineers, many of the people applying it, will be blue collar workers.

1:04 OSHA Comb. Dust Team: Dear Brad,
Thanks for your comment. Any input you can provide on helpful outreach materials would be appreciated. OSHA will spend a lot of time preparing materials before the final is published.

1:04 Comment From Roberta Stone: Currently, the cost of an explosibilty test is very expensive. Is there any plan to make the testing facilities more readily available and less expensive?

1:04 OSHA Comb. Dust Team: Roberta, thanks for your question. OSHA is considering the availability and cost of private testing in its economic analysis supporting the rule. OSHA anticipates that testing will remain in the private sector, and OSHA does not regulate private sector prices.

1:05 Comment From Jeff Philiph: Is there a minimum quantity of dust or size of operation where the risk of a dust explosion is not a significant concern? (for example, laboratories, research facilities, small maintenance shops)

1:05 OSHA Comb. Dust Team: Thanks Jeff,
The information we hope to get today will help us to answer exactly that question. As you can see from the question #1 above, OSHA is seeking information to help the Agency define where there are significant risks of combustible dust explosions and how we can develop the most effective standard for addressing those hazards. .Defining combustible dust is an important part of that process.

1:09 Comment From Charles Carr, Maryland: I recommend that new regulations are straightforward for manufacturing people to read and understand. They should start with the common situation that a facility has a manufacturing process that generates combustible dust. Perhaps it has been picked up in consulting, or enforcement visits. The new regulations should pick up from there an tell them in a straighforward and simple manner what is required for dust collection.

1:09 OSHA Comb. Dust Team: Thanks Charles, This is the type of information that we are looking for in response to our questions. Any concrete ideas you have would be appreciated.

1:09 Comment From Charles Kelly: Historical question for Dr, Michaels. When will OSHA post the discussion points from the previous Stakeholder meetings on combustible dust as was indicated at each meeting? These "notes" will be valuable resources for the general public to use as a reference when reviewing any proposed rule from OSHA on combustible dust.

1:09 OSHA Comb. Dust Team: Thanks Charles for writing in. The summer reports from each of the 3 stakeholder meetings are available on the OSHA website and on

1:10 Comment From Dave Padgett Sr.: What is the timetable you are trying to accomplish this standard in?

1:10 OSHA Comb. Dust Team: Dave,
The rule-making process is very complex and can be time consuming. However, OSHA is working as expeditiously as possible to complete this rule making. Our next step is to initiate the review under the small business regulatory enforcement fairness act (SBREFA) in April 2011.

1:10 Comment From Jeff Philiph: If a risk assessment is done to determine the appropriate precautions to take with a performance based approach, what is considered to be a tolerable risk for a combustible dust explosion?

1:10 OSHA Comb. Dust Team: Jeff, that is one of the things that we are trying to determine. OSHA standards must address significant risks.There are a lot of different factors to consider and there are numerous types of dust. OSHA is seeking your input.

1:12 Comment From Dr. Erdem A. Ural: Is it too late to submit comments through conventional means?

1:12 OSHA Comb. Dust Team: Dr. Ural--OSHA will continue to accept comments until the time at which the development of the proposed rule will be delayed.

1:13 Comment From SLG: What test methds (other than the sieve method) are required to determine if dust is "combustible dust" and when is testing required? e.g. if there are neve accumulations of greater than 1/32" is testing even required?

1:13 OSHA Comb. Dust Team: SLG, There are numerous test methods available and they are identified in NFPA and ASTM standards. OSHA has not determined which methods may be addressed in its proposed standard. We are currently open to any information that you could provide.

1:15 Comment From Mark Ellis: Another observation on the scope of the proposed rule . . . OSHA should exclude mineral dusts untreated or otherwise not impregnated with an OSHA- or National Fire Protection Association- (NFPA) listed combustible/flammable material. This qualification would preclude mineral dust treated with a recognized combustible/flammable material from “slipping through the cracks” with a blanket exemption. The suggested qualification also would preclude mineral producers or their customers having to send known nonflammable/noncombustible mineral dusts to facilities for explosibility testing, something regarded as both costly and unnecessary from a technical perspective.

1:15 OSHA Comb. Dust Team: Thanks Mark, This is the type of input that we are looking for in response to our questions. Any concrete ideas you have would be appreciated.

1:16 Comment From Mark H.: Using the Kst > 0 as the criteria for inclusion of a dust under the proposed standard is too broad and would include dusts that pose little risk. Is recommend considering the Bureau of Mines explosion severity and explosion sensitivity calculations which compare the dust explosiveness to coal. Dusts should be regulated under the OSHA standard if they meet the class II definition under this evaluation.

1:16 OSHA Comb. Dust Team: Thanks for the recommendation Mark H, we will consider it.

1:17 Moderator: Many of you are asking about the timing of any new regulation. Here is an answer we posted at 1:10 p.m.: The rule-making process is very complex and can be time consuming. However, OSHA is working as expeditiously as possible to complete this rule making. Our next step is to initiate the review under the small business regulatory enforcement fairness act (SBREFA) in April 2011. Monday June 28, 2010 1:10 OSHA Comb. Dust Team

1:17 Comment From Rick C Knight: it would be extremely helpful for OSHA to define not only combustible dust by material type but by particle size and concentration.

1:17 OSHA Comb. Dust Team: Hi Rick, OSHA is actively working on the definition of combustible dust. Thanks for your comments. We would like to know your reasoning for the definition that you propose.

1:17 Comment From Harold McMillan: For those that may not be familiar, there were dust studies done under the guidance of The Bureau of Mines back in the 1960's and earlier. The Bureau of Mines was absorbed into The Department of the Interior in the mid 1990's. any reprots would be accessible through that office.Several different types of dusts were reviewed.

1:17 OSHA Comb. Dust Team: Harold, thanks for the recommendation, we will look into it.

1:19 Comment From Cal/OSHA experience citing dust hazards 2000-2009: TIn this period some 71 inspections resulted in citations related to a dust hazard. About 19 of these inspections were initiated due to a deflagration, fire, explosion or combination of these. The 19 accident investigations of dust-related fires, deflagrations, and explosions involved a variety of dusts including: aluminum, magnesium, wood, rice bran, lead azide, mixed plastic/toner, protein, grapefruit, mixed gunpowder/paper/graphite, and other unspecified metals. Two accidents resulted in fatalities, one in each. An additional 16 persons were hospitalized as a result of these dust-related accidents, and an additional five non-hospitalized injuries were recorded. There were 22 code sections cited in relationship to the dust hazards. A total of $514,210 of initial penalties was issued for the dust related hazards in the 19 accident investigations

1:20 OSHA Comb. Dust Team: Mhorowitz, thanks for the comment.

1:21 Comment From Fred K.: Is there an existing "analogous" OSHA standard on which you are considering modeling the forthcoming CB standard?

1:21 : Fred,

One area for which we are seeking input is whether the combustible dust standard should be modeled after our PSM Standard. We also would like input on how the new Combustible Dust Standard would interface with our Grain Handling Standard.

1:22 Comment From Jess McCluer: How long will the SBREFA review take and will they finish that process before OSHA issues a formal proposed rule?

1:22 OSHA Comb. Dust Team: Jess, the SBREFA panel process takes 120 days, and OSHA will complete this process before the rule is proposed.

1:22 Comment From David: Does OSHA plan on proposing a regulation that covers all employers or focusing on industries such as food processors with a history of combustible dust issues?

1:22 Comment From Dave Padgett Sr.: How will a standard be applied for thickness of the dust when all types of dust are diffrent and create different concerns when accumulated

1:22 OSHA Comb. Dust Team: Hi Dave Padgett and David,
At this time, OSHA has not determined how it will define combustible dust, what levels of dust will trigger provisions of the standard, or who will be covered by the standard. OSHA hopes that the information it receives from individuals participating in this Web chat and the blog will help OSHA to make those types of determinations.

1:22 Comment From B.Burridge: Can you give us an estimate on timing for the new rule? We certainly understand it is a long process. What would the best estimate on timing be? Six months or a year?

1:22 OSHA Comb. Dust Team: BBurridge and Jason: Thanks for your question about how long it will take to get the final rule out. Rulemaking can be a lengthy process, but this rule is a priority for the agency. It is difficult to predict when a final rule might be published. The next significant step is gaining input from the small business entities via the SBREFA panel discussions, which are planned for April 2011.

1:26 Comment From Jim Baker: Puched enter key too soon - German Insurance Institute Website with excellent section on Explosive Dusts (select "open database") (Institute for Industrial Safety of the German Legal Accident Insurance (IFA)):

1:26 OSHA Comb. Dust Team: Jim Baker,

Thank you for the information.

1:26 Comment From Bill Rudersdorf: We've had our dust tested and it meets the definition of combustible dust. Our goal is to keep the amount of dust below 1/32" through ventilation and housekeeping. Our ventilation system was put in about 7-years ago to the tune of $40,000; will we need to replace it if we can't keep our dust levels below 1/32"?

1:26 OSHA Comb. Dust Team: Bill, the proposed standard is currently under development. We are seeking input on questions such as combustible dust action threshhold levels. There are a number of reasons why ventilation systems may need to be changed outside the scope of the dust containment. For example, ventilation systems themselves can pose combustion hazards. If you have any input along those lines we'd like to hear it.

1:26 Comment From NSC Focus Group: • Scope: All workers exposed to combustible dust risks deserve the same level of protection. Exceptions should not be made based on industry size or classification. Suggest using the Dust Explosion Classification referenced in OSHA’s Combustible Dust National Emphasis Program and repeated in its publication, “Hazard Communication Guidance for Combustible Dust” to objectively scale the controls needed in individual workplaces based upon the risk that is present. Testing of dust that could be combustible would be required to objectively measure the risk. Requirements could be made less restrictive for lower risk facilities. • Balance between performance and specification based requirements: Both types of requirements have their advantages. Specification standards would be useful in directing the diverse industries that handle combustible dusts to take prompt and well defined actions that could mitigate many risks. Explosions and fires in the grain industry have been greatly reduced since promulgation of specification requirements in 29 C.F.R. § 1910.272. Some performance based requirements would also be beneficial to deal with varying hazards across industries and to allow employers the ability to adapt new strategies to address hazards of combustible dust. A non-bureaucratic approach to incorporate elements from some Process Safety Management performance based tools (i.e., incident investigation and management of change) would be beneficial. • Economic impacts:

1:26 OSHA Comb. Dust Team: NSC--Thanks for your email. Please resend your email; much of it was cut off so we are unable to see it. Please send your infomation to

1:28 Comment From Brad Meushaw: THe Chemical Safety Board provided some recommendations in the past. Will you be following any of those? Will training of employees be a part of the new standard?

1:28 OSHA Comb. Dust Team: Hi Brad,
We have received many questions today regarding what types of provisions OSHA intends to include in the proposed standard. We have not made those determinations yet. The purpose of this Web chat and the blog is to get your ideas and recommendations about the most effective way that OSHA can develop a standard that is both protective and feasible.

1:29 Comment From Guest: The NFPA in most, if not all of it's standards concerning combustible dust calls for a highly detailed inspection, testing, and maintenance program. Will this be part of the new OSHA standard? And how about record s of these activities?

1:29 OSHA Comb. Dust Team: Guest--OSHA must consider them in writing this rule.

1:29 OSHA Comb. Dust Team: R Layman,
The proposed standard is under development. We are seeking input on scope and application.

1:29 Comment From R. Layman: Will such a standard apply to research laboratories working with such materials?

1:29 Comment From Jason Reason: One of the biggest questions I get during my inspections is whether or not the proposed combustible dust standard will be PSM based or have PSM requirements like PHAs and MOCs. Will OSHA include PSM requirements in the proposed combustible dust standard?

1:29 OSHA Comb. Dust Team: Hi Jason,
OSHA hopes that the information it receives from individuals participating in this Web chat and the blog will help OSHA to make those types of determinations. We have received stakeholder input for and against a PSM based approach, and are looking for additional input.

1:30 Comment From Charles Kelly, DC: I am concerned that until OSHA defines "combustible dust" many of us are illprepared to respond to various rulemakings that pose the question of OSHA including "dist" language in other standards. I reference OSHA recently proposed Walking/Working Surfaces where OSHA has requested information on including combustible dust in that particular standard. Having multiple standards addressing the same potential hazard is not only confusing but somewhat burdensome.

1:30 Comment From Arthur G. Sapper: Comment from Arthur G. Sapper, McDermott Will & Emery LLP,, representing the U.S. Beet Sugar Association (trade association); Industry sector: Food (including sugar) The PSM Standard would be a very inappropriate model for agricultural dusts, for which the hazards are well understood and have long been known and the technologies are mature and predictable. PSM originated in the chemical industry, which has novel, varied and often poorly-understood chemicals and technologies. Rather than write a new standard to cover agricultural dusts, OSHA should expand the coverage of its already-existing Grain Handling Standard to cover agricultural dusts generally.

1:30 Comment From Julie Plavka: Fundamentally, everyone should know that strict housekeeping rules and having enough staff for housekeeping are essential to prevent dust explosions. However, these are the first things that managers cut to save money. We need OSHA to give us clear tools to make sure that managers do not dodge vague rules on housekeeping. As seen in the grain handling standard manual housekeeping such as vacuuming or sweeping should be used to minimize the possibility of layered dust being suspended in the air. Each housekeeping program should specify the schedules and control measures which will be used to control dust emitted from the system. There have been documented procedures to reduce dust accumulations including: pneumatic dust collection systems, pressurizing the general work area to provide a lower pressure inside the enclosed area, the use of oil sprayed, or the use of water. An action level to activate the start of cleaning in a housecleaning segment is essential.

1:30 OSHA Comb. Dust Team: Julie--Good information. Thank you.

1:31 Comment From Eric Dorbeck: As you can see there is already a lot of readily available info regarding dust. This should be referenced and used by OSHA. In addition, any new rule should be very simple and straight forward.

1:31 Comment From Fred D. Straub: I rec you include a listing of suspect comb dusts using the listing found on the current OSHA comb dust poster (including those dusts currently missing that can be found in NFPA) regardless of particle size. This may simplify the new rule for most non-safety pros. Then, its a matter of the employer determining combustibility based on particle size, concentration and moisture. Since even large particles will likely break apart into fine dusts through mechanical action, the simple listing of all possible comb dusts may be a good start to the new rule.

1:31 Comment From Gordy Koch: Recommned that OSHA apply the standard heirarchy of controls, placing more emphasis on engineering controls for fugitive dust, and administrative controls (performance) for housekeeping dust, followed by PPE in that order.

1:32 Comment From Sam Rodgers: There are two types of hazards from a combustible dust cloud. First there is a hazard to a person inside the cloud from being burnt. Second there is a hazard to those outside the cloud from explosion overpressure causing the room or building to fail and fall down on them. The hazard to an individual might be evaluated based on the dust accumulation at that point, while the hazard to everyone in the building might be better evaluated based on the average dust accumulation.

1:32 Comment From Rob H: Our company uses or generates combustible dust at several of our facilities worldwide. We have looked at approaches that include defining a threshold quantity, above which some sort of PHA methodology shall be employed, but, given the small amounts of dust that present a combustible dust concern, our company has focused on housekeeping, maintenance, eletrical classifications and proper grounding/bonding.

1:32 Comment From Rusty C.: Being involved in several plant clean ups, it seems the risk for explosions is far higher when cleaning is being conducted. I would suspect a threshold of what is acceptable by industry would need to be promulgated. However, that determination might point toward continuous cleaning, which increases probablilty of an event. Could OSHA set a standard for dust emitting machinery and put the responsiblity on the manufacturer rather than facilities?

1:32 OSHA Comb. Dust Team: Rusty, thanks for your comment. OSHA's aware of the increased hazards during plant clean-up. We appreciate your comment mentioning controlling dust emitting machinery. We're looking for input on engineering and administrative controls.

1:32 Comment From Rick C Knight: Particle size greatly influences the explosivity, as does humity concentrations. most dusts would lose their explosivity properties with high moisture content, even far below total saturation. This could be a cost effective way of controlly the risk. In both cases (large particle size and moisture content) the rule should make allowances for some exemptions.

1:34 Comment From Gary Chambers: Given how far out, realistically, a combustible std is, I hope efforts will in the meantime increase to educate relevant industries -- including insurance carriers -- about the various potential causes for dust explosions/fires.

1:34 OSHA Comb. Dust Team: Gary, Yes OSHA has already developed and posted various guidance products on the OSHA Web page that will help employers and employees better understand how to identify and control combustible dust explosions. Please see our Web page on combustible dust and if you have any ideas about other products the agency could develop while we're in the process of developing a combustible dust standard, please let us know.

1:34 Comment From Ron: I agree with Charles. I would have been good for OSHA to generate questions and make them available prior to the chat for use to consider and respond too.

1:34 Comment From R. Layman: It would be helpful for the standard to address when laboratories are subject to the new standard and when they are not. Sometimes in a lab depending on the engineering control in place there could be a similar hazard, other times not. It would be good for the standard to clearly specify when the requirements would apply to a lab and when not whether that be when there is a certain concentration or when certain engineering controls meeting certain requirements are in place.

1:34 Comment From Phil Peters: It would be of value to include alternate means of combustibility testing such as particle sizing and characterization in the standard in addition to the compleete batter of testing.

1:35 Comment From Rachel Brutosky: As far as cost-effective administrative controls, we recommend implementing a comprehensive maintenance plan as an easy and cost-effective way of minimizing dust accumulations. But any rule needs to map out proper cleaning methods/machinery...many facilities still use dangerous shop-style vacuums, compressed air, brooms, etc.

1:36 OSHA Comb. Dust Team: FRED ASKED:
In the forthcoming CB standard, do you anticipate having any "grandfather" provi[...]sions for existing engineering controls?

Hi Fred,
We anticipate that some aspects of the new rule will be retroactive. However, at this time, we do now know what those requirements will be, or to what extent.

1:36 Comment From Jeff Philiph: I think a distinction needs to be made between whether a dust is combustible and whether there is a significant risk of an explosion or fire. Under the right conditions a low Kst dust could be a hazard, but if the accumulated amounts or concentrations are low, there would be no hazard. So Kst by itself is not a good indication of the hazard. It needs to be considered along with the conditions present in the process.

1:36 Comment From Gregg Grubb: Regarding grain dust, has there been a review of the explosions that have occurred in gran handling faclities to determine if there are inadequacies in the standard that may have led to conditions that resulted in the explosion? For instance, the grain handling standard speaks specifically about filter collection devices and their location, but provides no guidance regarding the cyclones - I have seen facilities where cyclones are located indoors, without special provisions such as explosion superession systems, because the grain handling standard does not specifically prohibit such a condition.

1:36 OSHA Comb. Dust Team: Thanks Greg,
OSHA has reviewed explosions in grain handling facilities before and after the standard was an implemented and found significant reductions in the frequency of explosions. OSHA welcomes comments you may have on the desirability of explosion suppression systems in the context of a proposed combustible dust standard.

1:37 Comment From Arthur G. Sapper: The NSC Focus Group“A non-bureaucratic approach to incorporate elements from some Process Safety Management performance based tools (i.e., incident investigation and management of change) would be beneficial.” I am not sure of what, precisely, is meant by a “non-bureaucratic” approach to management of change. Wouldn’t it be sufficient for dusts with well-understood characteristics and handled by well-tested methods (such as in the agricultural sector) that changes to dust-handling equipment be made by qualified persons? There is no reason to have a team approach as in the chemical industry.

1:37 Comment From Guest: Compliance assistance resources are a must. OSHA should consider of a decision-tree for determining the presence of a combustible dust, what engineering and/or administrative controls are appropriate, etc. This can cover different industries, operations, machinery, etc.

1:37 OSHA Comb. Dust Team: Guest,
OSHA will continue to issue guidance materials and the combustible dust rule will likely include a non-mandatory explanatory appendix. Please provide OSHA any specific information you suggest for decision trees or similar guidance.

1:37 Comment From B.Burridge: If the purpose of the standard is to ultimately make places safer to work, without excessive financial burden, the kst values will most certainly need to be considered. Also, since the testing will likely remain in pvt sector, the testing will need standardization as well.

1:38 Comment From Gordy Koch: Recommend that the regulation include that employers conduct an initial risk assessment, updated periodically, to show how initial dust emissions or accumulations were reduced over time.

1:38 Comment From Rachael: Will any of the NFPA standards on combustible dust play a role in the new standard?

1:38 OSHA Comb. Dust Team: Thanks Rachel, yes the NFPA standards may play a role in the proposed combusible dust standard. OSHA understands that many facilities are designed to these standards and will take account of that in the rule making.

1:39 Comment From Jason Reason: Is OSHA going to develop one combustible dust standard or several standards for different types of dusts (like NFPA currently does it)?

1:39 Comment From Eric Dorbeck: Would it be possible for OSHA to write a new rule that includes the option of either performance based approach or a prescriptive std?

1:39 Comment From Dave Padgett Sr.: Perhaps the standard could reference an MSDS report and give examples of how they should be completed and where to find the info. needed.

1:39 Comment From Enrique S.: Will OSHA recommend specific engineering controls to those affected or will they leave private industry to its own devices to determine the best course to resolving past combustible dust issues?

1:39 OSHA Comb. Dust Team: Hi Jason, Dave, Enrique, and Eric,
We have received many questions today regarding what types of provisions OSHA intends to include in the proposed standard. We have not made those determinations yet. The purpose of this Web chat and the blog is to get your ideas and recommendations about the most effective way that OSHA can develop a standard that is both protective and feasible

1:40 Comment From Sean H: A company may have many different processes that are similar, yet produce dissimilar dust potential based on their operation, machinery, environment etc… How will this be addressed to insure that hazards are identified without making each plant perform an assessment?

1:40 Comment From Dave Padgett Sr.: Keep in mind when putting together these standards that if you get carried away you will impact the largest employer we have and that is small business. Standards need to be looked at through the eyes of the small guy where cost is king.

1:40 Comment From Bill Rudersdorf: Follow Up Comment: Our industry's dust has been tested and classified as meeting the current definition of "combustible dust." Knock on wood - there is no known prior explosion caused by our industry dust. My concern is for businesses who try but yet cannot keep their dust levels below 1/32" despite exhaustive housekeeping efforts/plan AND have ventilation systems that met NFPA 654 specifications when it was installed (often times recently). The impact of having to install new and potentially explosion proof ventilation will be overly burdensome to our industry.

1:40 Comment From Safety Cowboy: Statement: I work as a safety professional in the food & beverage industry. We make our own bottles (polyethylene resin - blow mold operations). Bottles that are rejects can be ground up and reused as long as they meet food safety standards. The re-grind operation has the potential to create dust. The MSDS for the virgin resin states "may be combustible at high temperatures". We sampled the dust and came up with 0.03% combustible dust using the OSHA ID201SG Directive CPL 03-00-008, Loss On Ignition (LOI) – ASTM E2105 (Thermogravimetric Analysis (TGA)) as recommended by the lab we contracted. This was NOT an explosivity test. Our view is that although the result shows there was a small amount of combustible dust - - 99.4% of the sample we submitted was "retained" in the sieve, meaning - very little passed thru the sieve and what did was judged as being 0.03% combustible.

1:41 Comment From Gordy Koch: Does OSHA anticipate that information and training related to combustible dust will be incorporated into either the new combustible dust regulation, Hazcom, or Fire Prevention Plans?

1:41 OSHA Comb. Dust Team: Gordy, thanks for your question. We are seeking input regarding training provisions for the proposed combustible dust standard. Please provide any input you may have along these lines.

1:41 Comment From Rs: All dry collection systems pose a risk therefore utilizing NFPA 68. NFPA 91, and NFPA 654 as models are helful in determining the requirements of a ventilation system and this type of specifc criteria must be included in the standard to ensure that ventilation systems meet the design criteria outlined. Otherwise, businesses and industries do not have sufficient guidance from OSHA to install and maintain ventilation systems.

1:41 Comment From Ron: In addition to kst values there needs to be a threshhold limit on the amount present in the operation

1:41 Comment From Brad Meushaw: A decision tree as an appendix would be helpful.

1:41 Comment From Rick C Knight: Regarding the Kst level rating of dusts perhaps more accumulation should be variable based upon the Kst. i.e. the higher the Kst the lower the acceptable acumulation.

1:42 Comment From Ron: I like the initial risk assessment approach but there should be a standardized format to that assessment so that they playing field is the same across the board.

1:42 Comment From John Fiegel: OSHA should be sensitive when applying Engineering controls in a hierarchy as they have a high up front cost and require regular maintance.

1:42 Comment From Mark H.: I support modeling the CD standard on the PSM standard. This would allow a risk based assessment as opposed to compliance with presecriptive requirements which may error either on being overly restrictive or not restrictive enough depending on the characteristics of the dust and the manufacturing environment. I would also recommend allowing an compliance with consensus standards as demonstration of equivalency to compliance with the OSHA standard.

1:43 Comment From Mark Ellis: The lack of explosivity of mineral dusts in well documented. For example, limestone dust is used extensively to render inert combustible dusts, such as coal dust. Indeed OSHA, on page 54344 of the ANPR, recognizes the benefit of dilution with noncombustible dust as one of the counter-measures to mitigate combustible dust hazards: “28. Do your facilities or equipment have any of the following primary engineering controls to mitigate combustible dust hazards? … d. Dilution with noncombustible dust. … Noncombustible mineral dusts should be excluded from any OSHA combustible dust proposal. To that end, we proposed a definition of noncombustible dust and attached a number of International Chemical Safety Cards (ICSC)(U.S. National version) of representative mineral dusts. These mineral dusts have extremely high melting points and are recognized to be non-combustible.

1:43 Comment From Tom H.: Kst values should determine the level of performance based criteria.

1:43 Comment From Julie Plavka: Only well-trained workers will be able to be effective in looking into dust hazards, and reporting those hazards to the proper authority either the company or o OSHA. The new OSHA standard must include strong worker training requirements. It is important that employees be trained in the recognition and prevention of hazards associated with combustible dusts. Employees should understand the factors which are necessary to produce a fire or explosion. Employees should be made aware that any efforts they make to keep these factors from occurring simultaneously. The type, amount, and frequency of training will need to reflect the tasks that employees are expected to perform. Training should be provided every new employee, a refresher annually, when processes change, or when a job assignment change. As in NFPA 654 operating and maintenance procedures and emergency plans should be developed for combustible dusts. Employers with combustible dusts in their workplaces should be required to add regulatory text on the content, quality, and evaluation of training related to the combustible dust standard. In our experience, many employers do not provide ample time or adequate job-specific training to their workers, and rarely is the training evaluated for effectiveness.

1:44 Comment From Gordy Koch: Consider whether CSHOs will be equipped with the skills to make effective engineering control recommendations (such as moving dust collectors outdoors) or if this should be left to the employer to determine.

1:44 Comment From Sam Rodgers: The dust explosion classification scheme recommended in the dust NEP and currently in NFPA-499 is inappropriate for a regulation on general dust requirements and should be limited to electrical classification. This scheme is the Explosion Severity and Ignition Sensitivity. The problems are multiple. First there are parameters in each index that are not related to the rate of explosion or ease of ignition. Second, the indices draw a line in the sand with no connection to the proximity of persons to the hazardous situation or the building design that would presumably be safe. The aforementioned indices were only intended to determine if electrically classified equipment is warranted to reduce the likelihood of ignition by that equipment.

1:44 Comment From L Goodman: I propose that OSHA create a model non mandatory housekeping plan as an appendix to the regulation to assist small business in compliance. Address the heirarchy of wet method clean up vs. dry and establish prohibited methods

1:45 Comment From Linda Brossard: Has OSHA determined that specific NFPA standards (or other standards) will be incorporated into the final rule-making on combustible dust?

1:45 OSHA Comb. Dust Team: Thanks Linda,
OSHA is reviewing all of the consensus standards and is considering using some parts for the proposed standard, and possibly as compliance options. Any input you could provide would be appreciated.

1:45 Comment From Rick C Knight: I disagree with the staement "There is no reason to have a team approach as in the chemical industry." anytime their is a significant risk of explosion, the team approach is always best. Otherwise it allows for one individual too easily to over look an area of exposure.

1:45 Comment From Jim Baker: I think the NFPA std's should be used as baseline information in the OSHA dust std. - to do otherwise will create a lot of confusion in implementing - which rule will take precedence when there is disagreement?

1:45 Comment From Sam Rodgers: Many persons are focusing on KSt as determining the hazard of a combustible dust. This is technically incorrect. KSt only quantifies the rate of burning, not the total result. Some dusts burn fast but do not generate as much total pressure or create as large a fireball, so they are less of a hazard to a building. It is patently incorrect to base combustible dust hazards on KSt alone.

1:45 Comment From Joe A.: As mentioned earlier, some states have already begun enforcing combustible dust hazards without definitive rules in place. Moisture, size, makeup all effect these hazards, yet samples taken to determine hazards are not collected per existing protocols. There has been alot of confusion as a result. We would be in favor of a rule that gives clear expectations that address specific industries assuming paper dust, cellulous, wood, etc. all pose different hazards. Performance based rules are fine only if specific industries are addressed.

1:46 Comment From Sean H: One of the challenges we face is everyone wants a definition of what is combustible dust however we can not narrow the scope due to the many different products and characteristics of those products. The bottom line – we must protect workers. This responsibility should be on the manufacturer of the product and the employer. If we try and define what dusts are and are not, some will fall through the cracks.

1:46 Comment From Gordy Koch: Since dust is a fire and explosion hazard, I would prefer to see the regulatory emphasis be in the fire prevention regulations, or separately in the new dust regulations, rather than Hazcom.

1:46 Comment From Darrell Hornback: The CD standard must make housekeeping a priority and manadatory!

1:46 Comment From Ron Davis: Does OSHA have a clear definition of a combustible dust and does it differentiate between primary and secondary explosion risks?

1:46 OSHA Comb. Dust Team: Ron, while OSHA's NEP contains a definition currently being used for enforcement activities, the input we are seeking during this Web chat and blog is how OSHA can clearly define proposed combustible dust so that the standard will cover the hazards fairly and effectively.

1:46 Comment From Brad Meushaw: I would like to suggest that a new OTI class be developed along side the new standard in order to ensure equall enforcement and that the course be run continuosly until all involved parties are trained.

1:47 OSHA Comb. Dust Team: Brad Meushaw,
Thanks for your suggestion. OSHA will be looking for effective ways to educate both those covered by the standard and those who enforce it. Combustible dust is a complex issue and OSHA will be developing many types of outreach materials to help people understand how to comply with the rule and effectively control combustible dust hazards in their workplace. If you have other ideas about how OSHA can reach out to individuals and better help them understand how to identify and control combustible dust hazards, please let us know.

1:47 Comment From Julie Plavka: Employee involvement is essential to this assessment as they are familiar with the operations and the specific environments that can produce the most dust; OSHA’s PSM standard Appendix C (2) strongly encourages employee involvement. Workers are the first line of defense in preventing and mitigating fires and explosions. If the people closest to the source of the hazard are trained to recognize and prevent hazards associated with combustible dust in the plant, they can be instrumental in recognizing unsafe conditions, taking preventative action, and/or alerting management. It has been our experience that employees are more likely to comply with a policy or standard if they are if they are involved in the development of the policy or standard.

1:47 Comment From JJC: Small businesses will have difficulty with any standard that deals with complex and technical issues such as Kst, etc. Using something similar to the Grain Handling Standard would make much more sense and it has proved effective.

1:47 Comment From Marc Fleischaker: Your question about grain handling facilities is interesting, and the grain industry is very focused on safety. We are considering the issue of portions of facilities not currently covered by the standard, and while the safety record is strong throughout grain handling facilities, are prepared to consider and discuss that question.

1:47 Comment From Rachael: One of the best ways to find out what is needed in a rule is to examine/investigate dust explosions--look at the findings, the root and contributing causes to the explosion. These causes should not just look at the engineering controls but also design, human factors, and overall management systems. Major accidents occur because of multiple factors. The rule can then be designed to manage this multiple factors.

1:47 Comment From Safety Cowboy: Follow up to earlier statement from "Safety Cowboy": of the numerous catastrophic events listed by OSHA as being precipitated by a combustible dust episode...none appear to be linked to polyethylene dust in the food & beverage industry (blow mold operations)...I would want COSHO's to understand this so that inspections don't require over zealous and expensive testing where there is no direct link or hazard. It is my view as a safety professional that as long as an employer has done a risk assessment and instituted controls resulting from that hazard that should be deemed acceptable. For the scenario I've listed (PE blow mold regrinding), general housekeeping and regular inspections to confirm no build up of dust should be viewed as acceptable.

1:48 Comment From Sam Rodgers: In response to L Goodman, the hierarchy of clean up methods must be tempered by an understanding of the chemistry of the material. for instance, NFPA-654 ROC has indicated that vacuuming was the preferred approach for all dusts, yet the same committee will be proposing this is not the case for sulfur dust in NFPA-655. Regulation should not give a hierarchy without recognition of the specific material hazards. Not all combustible dusts are the same.

1:48 Comment From S. Glenn: As important to making sure Industry understands the stanadard (we would prefer performance based as it provides the flexibility to incorporate innovative and new technologies that we deep to reduce risk) by providing the correct tools and education, OSHA needs to make sure their own people understand the standard when issued. Having inspectors and regional manager's act without proper understanding can cause the best standard to loose effectiveness as industry complies with the words and not the intent.

1:48 Comment From Joe G.: One of the challenges to adopting an NFPA standard is that it gets updated every 2-3 years. While this is a good thing, it might not be practical for the agency to continue to do this, considering the time it takes to update and promulate standard under the Adminstrative Procedures Act.

1:48 Comment From L Goodman: The difficulty in defining a CD lies in that almost any finely divided powder will support combustion in some manner.

1:48 Comment From Rachel Brutosky: To reduce capital expenditures associated with dust testing, how about expanding the list of recognized explosive dusts under NFPA 499, and clarify or list specific areas where explosion-proof or dust ignition-proof equipment is “required,” “highly recommended” or “not necessary.”

1:49 Comment From Gordy Koch: Emphasis areas should be separated into fugitive dust and housekeeping dust. Reducing the first typically will impact the latter.

1:49 Comment From Brad Meushaw: We know that we need fuel (combustible dust) an oxidizer and an ignition source for combustion. Keep in mind that although an air/fuel ratio that would not allow combustion (lean or rich) may exist on given day, the next day a change in production or a disruption of some sort could alter that previously safe ratio. be careful with engineering controls that rely on air/fuel ratios as a compliance factor.

1:49 Comment From Brad Meushaw: All of todays commentors, if they have not already done should visit the website and watch the combustible dust videos.

1:50 Comment From NSC Focus Group: • OSHA has issued several general duty combustible dust citations based on a positive Kst test alone without additional testing of other hazard characteristics. Would OSHA be willing to consider data on other characteristics of the dust (e.g. minimum explosive concentration and minimum ignition energy) that may make the possibility of an explosion remote as defined by the evaluation procedure in NFPA 499? Put another way, if OSHA uses only the Kst test result is an employer wasting time and money by performing other dust explosion tests to better understand the characteristics of the dust?

1:50 OSHA Comb. Dust Team: Thanks NSC,
OSHA hopes that the information it receives from individuals participating in this Web chat and the blog will help OSHA to make those types of determinations. We are looking for additional stakeholder input on testing and test methods.

1:50 Comment From Steve Sallman: Many times, managers keep workers' representatives from being part of regular inspections of safety problems in the workplace. If this standard is going to make a difference, OSHA has to make really sure that managers include workers and their representatives in all inspections – not just tell them afterwards. What will you do to make sure that happens in this new standard, since that kind of rule does not exist in most OSHA standards?

1:50 OSHA Comb. Dust Team: Steve, employee participation is one area for which we are seeking input in the development of the combustible dust standard. Please provide any input you have regarding prospective employee participation provisions that would be fair and enforceable.

1:51 Comment From Jack B.: Will everyone who makes dust have to have it evaluated?

1:51 Comment From Jake C.: Are any companies grandfathered under the old regulations, or are all companies expected to be current with the regulations stated by OSHA.

1:51 OSHA Comb. Dust Team: Hi Jack B and Jack C,
We have received many questions today regarding what types of provisions OSHA intends to include in the proposed standard. We have not made those determinations yet. The purpose of this Web chat and the blog is to get your ideas and recommendations about the most effective way that OSHA can develop a standard that is both protective and feasible

1:51 Comment From Francois Tanguay: Based on reading all the post, it seems that all questions/concerns are already dealt with by the existing NFPA standards. Why not reference them, instead of creating a new sets of requirement that end users will have to live with. Which requirement might differ from NFPA's and create more future issues than anything else?

1:51 Comment From Eric Dorbeck: Many industries have been successfully dealing with combustible dusts for years. Study one or several of them and learn their best practices. Put those into a std.

1:51 Comment From Guest: We need to be careful with so-called "consensus standards" - there doesn't seem to be broad representation there, for one thing. NFPA standards may be helpful in some ways, but should not be the basis for a CD standard from OSHA.

1:51 Comment From Sam Rodgers: Using anything similar to the Grain Std would be "one size fits all" which is in direct contradiction to the foregoing comments about handling dusts differently. Pick a thickness, any thickness, for all dusts and you will surely be non-conservative for some and overly conservative for others as the properties of the dust, as relates to its potential consequences, are not included.

1:51 Comment From Greg Miller: While this is in the development stage, has there been any discussion as to harmonizing this statute with that of Europe or vise versa? It would seem that it would be easier to harmonize this going forward rather than after the fact.

1:51 Comment From Gordy Koch: Some companies have put their employees in FR clothing. OSHA should include how this determination (if any) will be made.

1:52 Comment From L Goodman: Foolw up to Sam Rogers. I absolutely agree with your statement. it is up to the employer to detemine the hazards in the workplace and take appropriate measures. however a model plan would work for the vast majority of workplaces as in the asbestos standards.

1:52 Comment From Eric Dorbeck: Why even test materials when it is known that they burn or that the dust is explosive? Examples: coal, flour, plastics, sawdust

1:52 OSHA Comb. Dust Team: Thanks Eric Dorbeck, some industries do indeed already assume that their products are combustible and develop programs based on that determination. One area for which we are seeking input is whether the OSHA standard should allow employers to assume dust is combustible to preclude testing. Please provide any input you may have.

1:52 Comment From Tony Downes: I disagree withth edstatement that "almost any finely divided powder will support combustion in some manner". If a material won't oxidize/burn, then it can't explode in dust form.

1:52 Comment From John Fiegel: It would be important to consider several characteristics of the dust in order to determine its explosiveness. Kst, MIE and MEC are all needed to get a true idea of what the actual hazard for a given process is. For example a dust producing process may have an elevated Kst and MIE but lack the MEC to have an explosion.

1:52 Comment From Sam Rodgers: You asked for a comment on a low KSt that would not be hazardous. The test method is one aspect of determining KSt, because it is important to understand if the dust cloud can propagate the flame front or the flame will go out. Testing in larger vessels allows more time/volume for the flame to go out, meaning that some dusts might be determined to be a hazard in a small volume, but not so in a larger volume more typical of actual rooms. The other part of the equation is "hazardous to the receptor". A dust cloud inside a piece of robust equipment does not present a hazard to a person outside the equipment because the equipment will not "explode". Similarly a low KSt dust might not present a hazard to a building because the normal openings in a building at doors and windows are large enough to relieve the energy without knocking down the building. The overall consequence must be evaluated, not just the hazard.

1:52 Comment From Joe A.: Please give consideration to the cost associated with compliance. Will older facilities will be required to upgrade their dust collection systems (with spark detection) and intrinsically safe motors located in hazardous classifications? This will prove to be very costly for some industries that do not presently recognize combustible dust hazards.

1:52 OSHA Comb. Dust Team: Joe-OSHA will give careful consideration to the costs of compliance and examine the economic feasability of any proposed rule. OSHA recognizes that retrofitting facilities can be very expensive.

1:52 Comment From Darrell Hornback: Many combustible dust hazards exist because managers/supervisors were never properly trained. It is vital that that workers and their representatives have a meaningful role in the companies inspections/investigations. How will the new OSHA standard include strict detailed rules to make sure the managers who are responsible for finding the problems are fully trained for the job?

1:53 OSHA Comb. Dust Team: Hi Darrell,
We have received many questions today regarding what types of provisions OSHA intends to include in the proposed standard. We have not made those determinations yet. The purpose of this Web chat and the blog is to get your ideas and recommendations about the most effective way that OSHA can develop a standard that is both protective and feasible

1:53 Comment From Francois Tanguay: It seems there is a disconnect in between OSHA and the states adopted codes, mainly the ICC. The owner of a facility having hazardous processes generating combustible dust, would end up finding the NFPA 654 standard, either through searching on the NFPA website for ‘Dust’; or through going the state laws and finding the required NFPA standards to meet. It seems OSHA does not recognize this existing regulatory link between the states laws and the NFPA standards.

1:54 Comment From Bruce C: I think what Rick is asking there are some dust out there, that in extreme situatons the dust could be combustible, such as coffee creamer, yet on a day to day basis this will not happen

1:54 Comment From Anne DeMasi: Will any deciions be tied to GHS?

1:54 OSHA Comb. Dust Team: Anne,
A number of participants today have asked how OSHA will address hazard communication issues related to combustible dust. As you may know, OSHA is currently conducting a rule making to revise its standard for hazard communication. In that rule making, OSHA has requested comment on how to address combustible dust hazards. In addressing that issue OSHA will seek to have consistency between both the hazard communication standard and a combustible dust standard so that OSHA has clear rules about how to effectively communicate the hazards associated with combustible dust.

1:55 Comment From Rob H: Our company use and/or generates combustible dust in several facilities worldwide.

1:55 Comment From K. Miller: How does H.R. 849 and its status affect OSHA's path forward on rule making on this?

1:55 OSHA Comb. Dust Team: K. Miller--If legislation regarding combustible dust passes, OSHA will evaluate the bill at that time and respond appropriately. In the meantime, OSHA is moving as fast as possible on a combustible dust standard.

1:55 Comment From Rs: Kst values should be required inclusion for the MSDS; however, to ensure that the average blue collar worker understands this, a housekeeping requirements section must be included. Will the new standard be modeled from the Grain Handling Standard? In my experience, the GHS is a good basic document that has been successful.

1:56 Comment From Jennifer S: I'm struggling with some areas of my facility where wood dust exists. I would like to see clarification on how will OSHA address combustible dust in areas that are not entirely enclosed, such as outdoor conveyors with open grating bottoms or buildings with open sides. If the possibility for dispersion/confinement doesn't exist, is the dust still an issue?

1:56 OSHA Comb. Dust Team: Thanks Jennifer S, in areas without containment, deflagrations and flash fires can still occur, creating a hazard to workers.

1:56 Comment From Gordy Koch: If an employer knows that their dust is combustible, such as a textile or wood product, they should be able to make that determination without testing.

1:56 Comment From Brad Meushaw: Bruce C. I would hate to visit that plant on the day it did happen.

1:56 Comment From Julie Plavka: Many combustible dust hazards exist because managers or supervisors were never trained or properly trained in the first place. We need workers and their representatives to have meaningful participation in the company's inspections and investigations.

1:56 Comment From Joe G.: Another way of potentially handling the regulation is to consider the similarity with 1910.119, that is listing combustible dusts and impacted industries. You could base the coverage on commodity chemicals (as a first pass) and those that have had previous events. 1910.119 used the NFPA hazard rating system and listed covered compounds.

1:56 Comment From RL: Define specifics for required upgrades to, maintenance plans and periodic monitoring for dust collection systems, inlcuding the spark and fire prevention/arrest systems in them. Please do keep in mind cost restraints of small businesses at the same time providing the guidance to ensure safe operation of such equipment.

1:57 Comment From Ken: To average small woodworking business owner your Acronyms are nothing but confusing, you need to be simple and use laymans terms with all your rullings and discussion.

1:57 OSHA Comb. Dust Team: Ken, Thanks we absolutely agree. The acronyms can be confusing and we will make every effort to make sure standard is as easy to understand as possible.

1:57 Comment From Rachel Brutosky: Manufacturers can assume dust is combustible (better safe than sorry) to forgo the costs associated with dust testing, but then they will spend more money on "combustible dust" equipment, which is often more costly, when it might not be necessary.

1:57 Comment From Mike Brook: Kst and dust testing is probably the best way to indicate the risk associated with a particular type of dust. Understanding the risk associated with your dust helps eliminate reasons for not complying to a standard. Breaking up areas of a new OSHA regulation into areas of housekeeping and production make a lot of sense.

1:57 Comment From Rs: Metals are a paticular problem that has not been addressed in this chat. Technical data sheets are often provided for industries but there are no requirements to address metal fines resulting from grinding, milling, etc. The use of a PSM model may help to address both the potential and the use of MIE, KST, or MEC. In my opinion, wastes must be considered in the promulgation of the standard. OSHA must consider placing the requirements for explosibility testing on the manufacturer of the product as was originally intended with HazCom. Currently, there is no requirement for disclosure of combustibiltiy on MSDS or Technical Data Sheets and no incentive for suppliers to add this data. The result is that an average product engineer has little or no idea that the materials they are considering have explosibility issues. Whatever the standard incorporates, the definition a combustible dust is critical to the development of the standard.

1:57 Comment From Sam Rodgers: I would suggest that OSHA regulation on the process equipment design (requiring explosion protection or prevention by a RAGAGEP technique) be applied going forward and that housekeeping outside equipment be applied retroactively.

1:58 Comment From Eric Dorbeck: Testing of dust is valuable. Many dusts have already been tested and are known as combustible/explosive. Incorporate that data by reference eg NFPA stds. Any dust that has no known test data should thus be tested by the employer. Very soon most all dusts will be known as tested. New materials then would only need to be tested. All test data should be submitted to OSHA to keep teh list. Keep a running list of all known combustible/explosive dusts

1:58 Comment From Guest: Not sure where Safety Cowboy is getting his information, but lowdensity polyethene has a MIE of >10mJ and a MEC as low as 10g/m3

1:58 Comment From Joe G.: We are using a boroscope to survey hard-to-reach areas in our ductwork and ancillary areas. It has worked very well to help us develop an action plan to address these issues.

1:58 Comment From Sam Rodgers: It is encouraging to see the various hazards from combustible dust mentioned individually, as the protection/mitigation for these hazards are different. This understanding should be included in any regulation, just as the IH hazards from the small particle size material are regulated separately.

1:58 Comment From Gregg Grubb: I would recommend at standard that provides an "action level" and a "PEL limit" approach. A definition of "combustible dust" should be derived that addresses the possibility of explosion and requires such basic principles as hazard assessment, employee training, housekeeping provisions, and possibly other unspecified administrative administive protocols. Another provision addresses the probability of explosion and addresses the institution of engineering controls to control the increased probability of of explosion. This could possibily reduce the cost of compliance for smaller facilities working with substances that are possibly explosive but do not exhibit a high probability of such an event. It would appear from other comments that a number of resrouces exist to aid in defining such an approach.

1:58 Comment From Guest 2: Provisions will be needed included in the standard for allowing safe use of compressed air to clean some equipment and machinery that cannot be cleaned safely by traditional means (i.e. by wet wiping or dust igntion proof vacuums). For example, a paper machine making tissue would put personnel at substantial risk to get inside the extremely large machine to clean by wiping and vacuuming. It is impossible from safety perspective to clean these machines appropriately without using compressed air as all points needed cleaning cannot be safety accessed. Compressed air cleaning is the safest way to clean these machines from a personnel safety risk perspective and is realistically the only cost effective way to perform cleaning. Please consider provisions addressing the safe use of compressed air for cleaning equipment that puts personnel at risk when cleaning using other reconginzed cleaning methods (such as wet wiping and vacuuming). Thank you.

1:59 Comment From Rob H: Do you see combustible dust in storage as an issue? It would seem that the issue is dust being used or generated during a process. We do not see how a threshold quantity can be defined, unless it is defined as a quantity per unit area of dust being used or generated. Then the question also begs to be asked is the rate dust is used or generated. Does that threshold amount kick in if the amount is generated or used every hr, or every year?

1:59 Comment From Rick C Knight: Regarding the training of employees, as i read it CB is presently covered in HazCom.

1:59 Comment From Guest: We received a mailing stating the following changes. NFPA 68 should be treated as legal code.

1:59 Comment From Brett: Has any thought been given to a national database for dust testing to lower the overall cost of testing?

1:59 OSHA Comb. Dust Team: Brett--Thanks for your suggestion. We are looking for feasible ways that OSHA can make the standard as cost effective as possible.

1:59 Comment From Guest: The BoM report is a good reference. A more up to date reference is this one:

1:59 Comment From RB: DSUT TESTING AND DEFINITION: There are lower cost tests to determine whether solid is "combuxtible" or not. (Screening tests) The expensive testing is to determine SEVERITY of dust cloud explosion, Kst, etc.

2:00 Comment From Darrell Hornback: Workers should not have the undo burden of additional PPE (FR Clothing) placed on them as a means of protection from CD except in vary rare or unusual cases. We would oppose the CD standard allowing PPE except in the absences of effective engineering controls/housekeeping

2:00 Comment From Emily Boucher: It would be helpful to see the standard seperately address the different dusts encountered: metal vs. wood...

2:01 Comment From S. Glenn: I have to concur wiht hte "action level" versus "PEL" level comment. Running plants that generate high level of dusts to ones that don't generate the dust in a month that is generated in a large plant in an hour means great flexibility is needed and based on risk, not specifiation of equipment or operation.

2:01 Comment From Sam Rodgers: NFPA 68 is a Standard, not a Code. It is only RAGAGEP unless your locality adopts it by reference in its Building code. As a Standard, it does not include the code adoption language in the text. NFPA can clarify that further.

2:01 Comment From Rick C Knight: Isn'tthe primary explosive risk limited to mfg and packaging operations?

2:02 Comment From Ron: I think this was a very god exercise. Are there any plans to continue this approach with this subject or others in the future?

2:02 Comment From Kathy: What is RAGAGEP?

2:02 Comment From Barb B: Would this standard apply to coal fired power plants?

2:02 OSHA Comb. Dust Team: Barb,
The proposed standard is under development. We have not made such determinations yet. The purpose of today’s web chat and the blog is to seek input about how OSHA can make these determinations most effectively.

2:03 Comment From Guest: RAGAGEP - Recognized And Generally Accepted Good Engineering Practices

2:03 Comment From Bruce C: My concern is with the composite industry and the effects this will have on the industry.

2:04 Comment From Scott H.: guest 2: wouldn't that only serve to move the CD to another location? A vacuum can contain the CD.

2:04 Comment From Joe G.: RAGAGEP stands for Recognized And Generally Accepted Good Engineering Practices. Specifically, OSHA 29 CFR 1910.119 (D)(3)(ii) states:The employer shall document that equipment complies with recognized and generally accepted good engineering practices. EPA RMP also refers to RAGAGEP in 40 CFR 68.73:Inspection and testing procedures shall follow recognized and generally accepted good engineering practices.

2:04 Comment From RL: If NFPA is referenced at any place in the new standard, since it costs to purchase those requirements, can OSHA purchase rights and then include any text a user would need to comply within the standard, please.

2:04 Comment From Jim Baker: Engineered control of dust (dust collectors, vacuums, ductwork) need to be isolated as much as possible from the workers - locate outside the building, or protected by blast barriers, and including pressure vents on the equipment. In facilities with air conditioning and handling dusts, combustible dusts will collect and accumulate both inside and outside the ducts, and they need to be designed to facilitate inspection and cleaning, as well.

2:04 Comment From John Fiegel: Just recognizing that a dust is risk does not give enough clarification for engineering controls. The levels of controls and their associated costs vary on the fugitive dusts combustibility.

2:04 Comment From Sam Rodgers: To Rick Knight - I would not agree the the primary risk is limit to mfg or packaging. In many use locations a larger average particle raw material is segregated and the fines are collected in a dust collector. That presents a hazard.

2:04 Comment From S. Glenn: Also something to consider, EPA has a certification program for laboratories (as do some States) to make sure the laboratory is operating withint certain quality limits. OSHA may want to consider something similar so that quality of testing in a critical area will be equivelent.

2:05 OSHA Comb. Dust Team: Thank you for your participation. We have had a lot of valuable input and questions. We had almost 400 participants, so we are sorry if we were not able to answer all of your questions.

We will be posting follow up questions regarding the development of a combustible dust standard on DOL’s new blog ( Please join us there through July 7th to keep this discussion going. We will monitor the comments and reply as necessary.

Please review the four questions posted at the beginning of today’s discussion by OSHA. We need your input on this.

Note that participants questions and comments posted above do not necessarily represent the view of OSHA or the Dept. of Labor.

Thanks again for being part of today’s discussion.

Correction: OSHA wishes to correct a misconception posted by RS at 1:57. OSHA's Hazard Communication Standard, including its MSDS requirements, applies to materials that present a combustible dust hazard. For additional information, see .

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