Author(s): Guy Colonna. Published on March 2, 2015.

PREPARING A NEW NFPA STANDARD requires a mixture of ingredients, some provided by the public and the technical committee, others provided by NFPA staff. The aim is that, in the end, we have developed a meaningful document that benefits the targeted occupancy or addresses a particular hazard. The path to completion can sometimes be unusual, as was the case with the new NFPA 652, Fundamentals of Combustible Dust, which is due to be issued this summer.

To ensure that certain deadlines were met, NFPA’s editorial team resorted to humor to catch my attention. I love soccer, and was fortunate to spend time in Brazil last summer at the FIFA World Cup, where I followed the progress of the U.S. side through the so-called “group of death.” When I returned to work, one of the tasks at the top of my list was to review the edits to the Second Revisions for NFPA 652 prior to balloting the committee. To help put me in the proper frame of mind, a colleague resorted to posting images of Cristiano Ronaldo, Portugal’s star player, around my office, with captions of him pleading “please have NFPA 652 finished.” The tactic worked.

NFPA 652 provides the general requirements for management of combustible dust fire and explosion hazards, and directs the user to NFPA’s industry or commodity-specific standards, as appropriate: NFPA 61, Prevention of Fires and Dust Explosions in Agricultural and Food Processing Facilities; NFPA 484, Combustible Metals; NFPA 654, Prevention of Fire and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids; NFPA 655, Prevention of Sulfur Fires and Explosions; and NFPA 664, Prevention of Fires and Explosions in Wood Processing and Woodworking Facilities. The new standard establishes the relationship and hierarchy between it and any of the industry or commodity-specific standards, ensuring that fundamental requirements are addressed consistently across the industries, processes, and dust types.

Combustible Dust: Solutions Delayed

CSB safety video about a fatal combustible dust explosion at the AL Solutions metal recycling facility in New Cumberland, West Virginia.Courtesy: USCSB YouTube Channel

That consistency is essential, since dust-related fires and explosions continue to impact a range of industries—and the people who work in them—around the globe. In the U.S. alone, according to the U.S. Chemical Safety Board (CSB), 50 combustible dust accidents, resulting in 29 fatalities and 161 injuries, occurred between 2008 and 2012. Those included a 2010 incident at A.L. Solutions in West Virginia, where titanium dust resulted in an explosion and fire that killed three workers; the 2011 incidents at the Hoeganaes metal powder plant in Tennessee, where three combustible metal dust accidents that year killed five workers; and the 2012 flash fire at a U.S. Ink plant in New Jersey that injured seven workers, which a CSB investigation attributed to the accumulation of combustible dust inside a poorly designed dust collection system that had been put into operation just four days before the accident. Last August, aluminum dust was blamed for a catastrophic explosion at an automotive parts factory in Jiangsu, China, that resulted in the deaths of 146 workers and injuries to scores more. In January, the CSB used the public meeting announcing the completion of its U.S. Ink report to once again highlight the need for a “national general industry combustible dust standard.”

How we got here

While NFPA addressed combustible dust hazards and safeguards for flour and pulverized fuels, such as coal, as far back as 1920, it wasn’t until 2003 that users from all sectors comprehensively examined the specific requirements contained in the five commodity-specific NFPA standards. Those documents apply broadly to varied facilities, processes, equipment types, and dust types in order to protect against the hazards from combustible dust fires and explosions.

A basis for safety embedded in each of those standards requires the fuel—in this case dust—to be managed, ignition sources to be controlled, and impact from an explosion to be limited through construction, isolation, and housekeeping. The CSB highlighted those standards in each of its investigation reports in 2003 and in its 2006 combustible dust study. Among its conclusions was that “incidents would have been prevented or consequences mitigated” if the facilities had complied with the relevant NFPA standards. The CSB also recommended that the Occupational Safety and Health Administration (OSHA) develop a comprehensive federal standard to address the myriad workplace hazards found in facilities where combustible solids are handled, used, or stored in a manner that has the potential to generate and release combustible dusts.

Inferno: Dust Explosion at Imperial Sugar

On February 7, 2008, fourteen workers were fatally burned in a series of sugar dust explosions at the Imperial Sugar plant near Savannah, Georgia. This CSB safety video explains how the accident occurred.Courtesy: USCSB YouTube Channel

That recommendation remained in place without regulatory action by OSHA until 2008, when a tragic explosion and fire destroyed an Imperial Sugar refinery near Savannah, Georgia. The event claimed 14 lives and injured nearly 40, but it was also instrumental in helping overcome the inertia that had prevented any movement on a federal combustible dust standard. In March 2008, a revised and more robust national emphasis program for combustible dust was issued by OSHA. It provided guidance for the OSHA compliance teams on how they should inspect facilities where combustible dusts might be present. It incorporated the NFPA commodity-specific standards in two ways: to aid compliance officials in determining where combustible dust hazards might be found, and, where hazards are identified, to serve as a feasible means for abating those hazards. The momentum towards developing a regulation continued in April 2009 with the announcement that OSHA would initiate the rulemaking process in order to develop a federal standard.

In October 2009, OSHA published an advance notice of proposed rulemaking, or ANPR. While the ANPR asked a number of questions, several of them specifically sought comment on whether to simply use the existing NFPA standards, either through incorporation by reference or by permitting employers already in compliance with the applicable NFPA standard to be considered as complying with any OSHA regulation that would be developed. The commentary and questions further suggested that, while NFPA publishes several documents enabling unique industry processes and dust types to be addressed individually, the approach may also contribute to confusion and possible inconsistent requirements between standards.

Global Problem timeline
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In response to this perceived challenge to the longstanding NFPA combustible dust standards, NFPA staff addressed the question of whether there was a better way to structure the committees and standards. Working through the direction of the NFPA Standards Council, a task group chaired by a member of council explored options for restructuring the combustible dust project. The task group consisted of the chairs of the four existing, commodity-specific standards technical committees, an additional member from each committee, and NFPA staff liaisons. A report was presented to the Standards Council at its March 2011 meeting that contained two key recommendations: the establishment of a correlating committee to oversee the work of the four existing combustible dust committees, as well as the work of a proposed new committee on fundamentals; and the establishment of a new technical committee whose scope would permit it to develop documents on the management of hazards from combustible dusts and combustible particulate solids.

For any NFPA standards activity, the scope frames the work of the committee as it executes its charter, namely the development of one or more documents. With the creation of the correlating committee, an extra layer of oversight was added to the combustible dust document family to be more responsive to the challenges made as part of the OSHA narrative in the ANPR.

According to the scope of the correlating committee, the group was given responsibility “for documents on hazard identification, prevention, control, and extinguishment of fires and explosions … in facilities and systems” involved with “combustible particulate solids, combustible metals, or hybrid mixtures.” While that scope is broad, that of the new technical committee on dust fundamentals is limited to “information and documents on the management of fire and explosion hazards from combustible dusts and particulate solids.”

The committee on fundamentals began its work in earnest in early 2012, using task groups to develop draft chapters based on a straw-man outline proposed by the committee. A preliminary draft was developed and approved by the committee to serve as the basis for requesting approval from the NFPA Standards Council to establish a specific revision cycle. The Council initially approved the development of NFPA 652 for the Fall 2014 cycle; during the second draft stage of the process, however, the committee requested more time to review and process the extensive public comments received. That request was approved for the Annual 2015 cycle, which is where the new standard currently remains.

With the completion of the NFPA 652 Second Draft in May, other combustible-dust standards activities began. Three of the industry or commodity-specific standards entered the Annual 2016 revision cycle and held their First Draft meetings last summer. One of their tasks was to consider the impact of NFPA 652 on their documents. At the same time, the correlating committee met to review and approve the Second Draft of NFPA 652 and the First Drafts for NFPA 61, NFPA 654, and NFPA 664. In the three years since this restructuring process began, the important first steps toward developing consistency within the NFPA combustible dust standards have been taken.

Going forward

The benefits of the formal hierarchy outlined in the new NFPA 652 result when an industry or commodity-specific standard must justify why some “fundamental” provisions in the standard are not applicable to a specific industry. Throughout the standard, requirements are linked to lessons learned or findings reported in investigations by the CSB and elsewhere.

For that reason, hazard awareness appears prominently within the standard through the inclusion of chapters on hazard identification, hazard analysis or evaluation, and hazard management involving hazard prevention or mitigation. Both the CSB and OSHA raise concerns with the retroactivity statement that generally appears within NFPA documents using approved “boilerplate” language, which states that the provision applies throughout the document to new facilities only unless modified. Using the lessons learned and the agency comments, the committee made some of the requirements in NFPA 652 apply retroactively.

223330 BA_Omaha World _opt

Grain dust was blamed for an explosion at an animal feed facility in Omaha, Nebrask, in January 2014 that killed two and injured 10. Photo: Brynn Anderson; The World Herald

The most controversial provision to be applied retroactively is the dust hazards analysis, or DHA. The standard defines DHA as “a systematic review to identify and evaluate the potential fire, flash fire, or explosion hazards associated with the presence of one or more combustible particulate solids in a process or facility.” For existing facilities, a DHA is permitted to be phased in and completed not later than three years from the effective date of the standard. Because so many of the investigation findings conclude that owners/operators appear to be unaware of the hazards posed by combustible particulate solids that have the potential to form combustible dusts when processed, stored, or handled, the committee believed it was essential to establish the DHA as a fundamental step in creating a plan for safeguarding such facilities.

While these steps and others demonstrate NFPA’s active focus on safeguarding against combustible dust hazards, there has been little progress on the regulatory front. OSHA announced at the end of 2014 that the combustible dust rulemaking was no longer on its list of active regulatory projects, citing other priorities. In an op-ed that appeared in The New York Times in August, Dr. Rafael Moure-Eraso, chairman of the CSB, decried the series of laws, executive orders, and judicial barriers that have “virtually paralyzed” the government’s ability to issue new safety standards. “According to a nonpartisan congressional study, the process can take nearly 20 years from start to finish,” Moure-Eraso wrote. “Given those conditions, is it any wonder that a recent RAND Corporation report found that American workers are three times more likely than their British counterparts to die on the job? ... I believe that OSHA’s leadership wants to move forward with a combustible dust standard just as much as we do. But as its director, David Michaels, recently told NBC News, ‘We have a standards process that is broken.’”

While a comprehensive federal standard for combustible dust no longer seems likely with that announcement, the fire and explosion hazards from combustible dusts continue to exist, and they present a credible risk within facilities across a range of industries. Commenting on the CSB release of its U.S. Ink report, Moure-Eraso said that an OSHA standard “would likely have required compliance with National Fire Protection Association codes that speak directly to such critical factors as dust containment and collection, hazard analysis, testing, ventilation, air flow, and fire suppression.” NFPA believes that its standards continue to address those critical factors.

Perhaps the time is right for OSHA to add NFPA 652 to its national emphasis program, or to take other steps to encourage industries to comply with NFPA standards.

GUY COLONNA is NFPA's division manager of industrial and chemical engineering.