Sunday, April 21, 2013

Metal Dust Ignites Fire at Manufacturing Facility

Metal Dust Ignites Fire at Manufacturing Facility
From Harrington Group, Inc.

 Metal Dust Ignites Fire at Manufacturing Facility

Posted on Thursday, March 28th, 2013 

Earlier this month, metal dust ignited and burned inside duct work at a RSA Engineered Products manufacturing facility. RSA designs and manufactures components and assemblies for military and commercial aircraft OE manufacturers, systems integration companies, and several government entities around the world. Their products have been a part of various types of aircraft for over 50 years.

The fire in the Simi Valley facility was reported around 10am on March 5th when employees noticed smoke coming from a vent in the ceiling and called 911. Approximately 70 employees were evacuated from the facility, but no one was injured.  About 40 firefighters, police officers, and hazmat team members reported to the scene. According to fire department officials, the machine shop in the facility has a dust collection system that expels metal dust through ducting and the fire involved metal dust inside the duct work. Captin Mike Lindberry of the Ventura County Fire Department stated, “Dust from metals is highly combustible, and if it comes in contact with a heat source, you can have quite a fire.”

Metal dust fires cannot be extinguished in a traditional manner, as they are water-reactive. Instead of suppressing the fire, it can react violently and grow larger if water is applied. Hazmat teams were brought to the scene to seal off both sides of the duct to eliminate the ability of the fire to travel. The fire suffocated itself by approximately 11am as it burned out all of the fuel and oxygen within the duct work. Firefighters kept watch inside the ductwork using thermal imaging cameras to confirm that the heat was cooling off and that no additional measures were needed.

Employees of RSA were allowed to return to the facility, which suffered little damage, once firefighters determined that the air was free of hazardous gases. As part of decontamination, the firefighters who entered the building were also hosed down to ensure that no hazardous materials had entered their respiratory system.

The initial cause of the fire remains under investigation.

Saturday, April 20, 2013

Fire at Wooden Pallet Yard Causes $2.5M in Damages

Fire at Wooden Pallet Yard Causes $2.5M in Damages
From Harrington Group, Inc.

Fire at Wooden Pallet Yard Causes $2.5 Million in Damages 

Posted on Friday, June 15th, 2012

In May, a fire ripping through a 10-acre wooden pallet yard and spreading to a nearby tire center, caused an estimated $2.5 million in damages. Nearby residents were evacuated, but thankfully, no one was injured. The fire started at Pallet Market, Inc. in Fontana, California. Pallet Market supplies wooden pallets and pallet related services to various industries, including food, office, and logistics. The business opened 10 years ago will have to close, at least temporarily, until they can figure out what to do next. Pallet Market employed 60 people.

Authorities say the yard was full of thousands of dry wooden pallets, stacked hundreds high. Residents said that smoke could be seen for miles.Flames burned 80 feet high and took over five hours to get under control. Approximately 170 firefighters and 25 engine companies reported to the scene. The fire started among the stacks of pallets and then spread to a storage yard containing semi-truck tires. Several small explosions, most likely the result of propane tanks that power forklifts, made firefighting efforts difficult.

The pallet yard was completely destroyed, along with an adjacent warehouse and a tire center warehouse. The manager of Pallets Inc. stated, “It’s done. We’ve got nothing to ship anymore”. The manager of the tire center said that he had never seen a truck center fire in the 25 years he’s been in the business and while there was significant damage, the center would be able to overcome and continue with business as usual.

The incident is still under investigation, however initial reports indicate that the fire was started by a welding operation earlier in the day.

Tuesday, April 16, 2013

Spark Detection: First Line of Defense for Preventing Combustible Dust Fires and Explosions

Spark Detection: Your First Line of Defense for Preventing Combustible Dust Fires and Explosions

Our article on Spark Detection as published in Powder/Bulk Solids

Spark Detection: First Line of Defense for Preventing Combustible Dust Fires and Explosions

According to the National Fire Protection Association (NFPA) Standard 654, the Standard for the Prevention of Fire and Dust Explosions (2013 edition), combustible dust is defined as “a finely divided combustible particulate solid that presents a flash fire hazard or explosions hazard when suspended in air or the process-specific oxidizing medium over a range of concentrations.” The dust may be from organic or non-organic matter in any combination, and a dust explosion can have the same impact as a gasoline explosion. The key to avoiding a catastrophic event is to install an effective prevention technology for detecting all sparks and embers in the incipient stage in the process material flow, and extinguishing or diverting any sparks before they ignite the transported material and dust.
Spark detection and extinguishing systems are comprised of detectors, a control console, and countermeasure devices like extinguishment or high-speed abort gates. When a spark or ember enters the field of view of a detector, the detector sends a signal to the control console. The control console sets an alarm, records the event, and triggers the countermeasures. There are multiple countermeasures possible but the typical application is for the control console to activate an extinguishing device that sprays atomized water for a set period of time to extinguish the hazard without affecting production.

Detector Technology
Different types of spark detection systems have been developed offering varying degrees of protection. Two broad categories of these: sensors that detect light in the visible and invisible near infrared range and those that detect heat radiation. In the heat category are black-body radiation detectors. All bodies radiate energy proportional to their absolute temperature. As the temperature of a black body increases, it emits electromagnetic radiation at higher intensities and shorter wavelengths.

    Detectors that sense only heat cannot detect sparks or embers until they reach a certain minimum temperature, and are in close proximity to the sensor. Fire prevention systems based only on heat detectors rely upon the theory that only particles above a certain temperature are dangerous, and only those particles need to be extinguished. These detectors might miss sparks that, combined with proper conditions for combustion which materialize farther downstream, may still result in a fire or explosion. The only way to be sure that a spark is not going to create ignition in the process is to detect and extinguish all sparks. Because of this, the NFPA specifies in its Standard 664 paragraph A., “The spark extinguishing system should activate every time a single spark is detected.”

    Industry expert, Dr. Vahid Ebadat of Chilworth Technology Inc., a firm that investigates explosions, concurs, saying, “The ‘bottom-line’ response to this question would be a suggestion to consider the above-quoted guidance from NFPA 664, and detect and extinguish every single spark”.

    The preferred technology for spark detection in most applications is to utilize detectors that are designed to detect light energy in the near infrared (IR) range, as proven in over 200,000 successful installations worldwide. This methodology is more effective at identifying possible ignition sources in the incipient stage, before combustion starts. Spark detectors see the infrared energy emitted by a spark, and because of the properties of infrared light, it can see sparks and embers through many types of material and even reflections of embers that heat detectors cannot. Light from a spark or ember in the near infrared range can also be detected at much greater distances than heat.

Heat radiation becomes harder to detect the farther the detector is form the source. According to the Inverse Square Law:

    For point sources, intensity of the radiation varies inversely with the square of the distance from the source. Doubling the distance reduces intensity of the radiation by a factor of four, (1/4 of its original value).
    In other words, at twice the distance from the detector, an ember must be four times as intense to be detected by a black body detector. Available black body heat detectors are typically limited to less than 30 in., whereas some infrared light spark detectors can detect hazardous conditions reliably in large ducts and transitions much greater than 30 in.

    In heavy product flow, the material inside the conveyor or duct can act as insulation and mask the heat signature from a spark or ember and thus these hazards can pass the heat detector without being detected. Black body or “hot particle” heat detectors are best suited for applications where there is ambient light present, such as drop chute transitions onto or from belt conveyors with detectors viewing through the cascading material on opposite sides of the chute. This configuration of two opposing heat detectors versus one single detector provides a far greater detection area and greatly reduces the material masking effect.

Detector Applications
Because of the wide variety of materials being transported in ducts and the varying duct shapes and dimensions involved, different types of IR spark detectors have been developed for various applications. 

    Low-pressure pneumatic conveying systems with ambient air temperatures use a standard IR spark detector. The example shown in Figure 1 mounts onto the duct and detects sparks and embers through the material stream.

Figure 1

    For applications involving high temperature or high pressure conveying, IR spark detectors using stainless steel clad fiber optic cables connecting it to the duct cross sectional viewing area should be used. Using fiber optic cables protects the sensor electronics from the radiant heat of the transport or conveyor from a material dryer or other heat source. The cable-equipped sensors shown in this example can detect sparks and embers in air stream temperatures up to 660ºF, and 1200ºF with a special adapter – without the use of cooling air.

They can also be applied to high-pressure and dense-phase transport systems where a denser material flow is normal and the material abrasion of the sensor lens may be a problem. In this case, these fiber optic cables use a hard blue sapphire lens to protect against abrasion.

    In applications where ambient light is present a black body radiation detector is used. One application, a pellet mill for example, is at the outlet of a pelletizer and inlet of a cooler to detect embers and overheated pellets. Two opposing sensors are preferred to ensure the full coverage of the material stream. For high-temperature applications a special version of these sensors is fitted with fiber optic cable. The third type of black body sensor has a higher spectrum response for special applications.

Detector Mounting
The manner in which detectors are mounted on ducts also makes a difference. In the interest of achieving a maximum field of view, some black body sensors employ rounded globe type lenses that project into the duct and material flow (see Figure 2). Depending on the type and size of material, this exposes the lens to abrasion that wears through the lens until the sensor is compromised and its components are exposed to the environment within the duct. These conditions affect the sensor’s ability to function properly and make the system unreliable over the long-term.

Figure 2

    A better way to achieve the required visibility, while reducing the exposure of the sensors to wear and tear, is to use sensors with flat lenses and mount them flush on opposite sides of the transport duct (see Figure 3 and 4) where the material flow helps keep the lenses clean. Using paired IR detectors on either side of a duct has the benefit of ensuring redundant detection from different viewing angles throughout the duct section.

Figure 3

Processing Plant Application
A large processing plant will use multiple spark detector pairs in different key locations. One example, the wood pellet mill shown in Figure 5 includes detectors at the output of the dryer, the hammer mill, pellet press, and cooler, as well as the conveying systems between each production process, and all dust collection systems. Atomized water extinguishment systems with plug-free nozzles are used in some areas and fire dump valves are used to remove burning materials from the process. Other countermeasures can be triggered including deluge valves, abort gates, equipment shutdown or programmable logic controller (PLC) actions. These are accomplished using advanced control consoles.

    Advanced multi-microprocessor control consoles can monitor and alarm on various hazardous conditions with the processing plant using various type of detection. Other possibilities include smoke detectors, rate of heat rise detectors, combustion gas detection, flame detectors along with the standard IR spark detectors and black body radiation detectors. These advanced control consoles can also trigger multiple combinations of countermeasures from multiple detection zones and can be setup for complex special configurations.

Industrial Equipment Approvals
Process industry professionals know that when a technology is Factory Mutual Approved, it has undergone extensive testing to ensure it delivers on its promise and is reliable. Fire and explosion safety equipment that is FM approved has been certified to reduce risk of property loss and as an added benefit many insurance companies provide discounted rates. When choosing any type of safety system, one should consult with the supplier to ensure that not only the correct technology is being installed, but that the equipment meets the highest industrial safety standards as well (see figure 4).

Figure 4

    Awareness is the key to fire and explosion prevention, and the key to protecting material transport systems is in understanding the effectiveness of different spark detection technologies. With an eye to reliable safety, IR spark detectors have proven effective in providing maximum safety in helping prevent fires and explosions in the process industries.

    Jeffrey C. Nichols, managing partner, Industrial Fire Prevention LLC, process safety specialist, has been helping to prevent industrial conveying and dust collection system fires and explosions since 1979. For more information, visit, e-mail, or call 770-266-7223.

Thursday, April 11, 2013

Dust Collector Fire and Explosion Highlights Need for Combustible Dust Considerations In System Designs |

Dust Collector Fire and Explosion Highlights Need for Combustible Dust Considerations In System Designs

Dust Collector Fire and Explosion Highlights Need for Combustible Dust Considerations In System Designs

A massive fire and explosion in the dust collection system of a New Hampshire wood pellet manufacturer demonstrates the need for adequate system design to prevent combustible dust explosions in general industry.

May 16 2012 – Editorial | We recently published a news article on about OSHA’s enforcement actions concerning last year’s combustible dust fire and explosion at the New England Wood Pellet Company’s Jaffrey, New Hampshire wood pellet plant.

On October 20 2011, a combustible dust fire began in the wood pellet cooler, most likely caused by a spark or ember from the pellet hammer mill. The fire then spread through the ductwork throughout the plant, eventually reaching the dust collector causing it to explode. When the collector exploded, the explosion vented through the baghouse’s explosion vents into adjacent storage silos setting them ablaze further spread the fire throughout the plant. More than 100 firefighters and emergency personnel from at least 14 towns worked for over 15 hours to put out the blaze.

The OSHA report outlines specific areas where the plant lacked adequate spark detection devices, fire suppression systems, and explosion venting/protection within the dust collection system. The fact that the plant had been cited by OSHA for several of the same issues previously after a 2008 incident, led to OSHA assessing total fines of $147,000.
Examining what went wrong in this incident highlights the need for diligence on the part of plant management and operators regarding the dangers of combustible dust.

What Went Wrong?

The October 20 2011 fire and explosion at the Jaffrey, NH plant was not the first combustible dust related incident at the plant. In 2008 the plant experienced a similar fire and explosion that caused more destruction than the most recent one. After completing its investigation, OSHA at that time fined the plant over $100,000 for safety violations that led to the fire. Subsequently, the plant, in an attempt to prevent another such occurrence, “retained engineers and consultants, and spent over $2 million on various improvements to enhance worker safety at its Jaffrey facility” according to a release from the company. This apparently including the installation of some explosion isolation devices in the ductwork (Rembe explosion isolation device) and installed explosion protection (explosion vents) on the baghouse. However the company’s effort and expense failed to prevent another incident from occurring.

Fire fighters work to put out a massive blaze caused by a destructive combustible dust fire and explosion at the New England Wood Pellet Company's Jaffrey, NH facility.
Fire fighters work to put out a massive blaze caused by a destructive combustible dust fire and explosion at the New England Wood Pellet Company’s Jaffrey, NH facility.
The OSHA report is quite thorough in its description each poorly designed, installed and operated part of the dust collection system either caused or intensified fire and subsequent explosion.

For example the report cites the plant for 2 main offenses. The first one is regarding poor housekeeping throughout the plant that led to large accumulations of combustible wood pellet dust forming on top of machinery (such as the pellet cooler where the fire began) and on elevated surfaces such as overhead rafters, ceiling joists, troughs, etc. Secondly, and more seriously, the plant was cited under the General Duty Clause of the OSHA Charter* for failing to take reasonable steps to prevent a combustible dust fire/explosion from occurring. OSHA cited several industry standards such as the National Fire Protection Association building code that the plant failed to heed in the design and construction of the plant’s dust collection system.

Ductwork Lacked Sufficient Spark Detection, Fire Suppression, or Explosion Isolation Devices

A major oversight in the ductwork system, was the lack of appropriate spark detection, fire suppression or fire isolation devices on all of the ductwork between the various machines throughout the plant. For instance, OSHA reported that the connecting ductwork between the pellet hammer mills, the pellet cooler, the bucket elevators storage silos and most of the dust collectors in the plant had no spark detection system, fire suppression system, or explosion isolation devices installed. The only control device the plant had was an explosion isolation device on the conveying duct between the pellet cooler and the pellet cooler baghouse. However, the device did not function properly and allowed the fire to propagate further downstream into the baghouse.

NFPA 664 (2012) Prevention of Fires and Explosions in Wood Processing and Woodworking Facilities: 8.2.1. and Hazard Determination – Conveying systems with fire hazards should be isolated to prevent propagation of fire both upstream and downstream (OSHA isolation can mean spark detection and suppression). Prevention of Fire Extension: When limitation of fire spread is to be achieved the following criteria shall be demonstrated…(4) Particulate processing systems (dust collection systems) shall be designed, constructed, equipped and maintained to prevent fire or deflagration from propagating from one process system to an adjacent process system.

Additionally, the ductwork was not engineered and/or constructed to sufficient strength to withstand the maximum anticipatable explosive pressure resulting from a conflagration involving its intended payload (combustible wood dust). This led to the duct bursting open, releasing the explosion into the plant near firefighters and may have been a contributing factor in the fire by-passing the isolation device.

NFPA 664 (2012), Sets forth alternative safety criteria for ducts with a deflagration hazard, to ensure that the ducts are builds with a sufficient strength and with appropriately sized/located protection devices to handle the maximum expected pressure generated by a dust explosion. 

Baghouse Was Not Adequately Protected Against Explosion Hazards

The plant recently installed explosion vents on the baghouse explosion vents.* However, the design and installation of the explosion protection on this particular baghouse may actually made things worse than if there had been none at all.

When the fire reached the baghouse and caused the finely dispersed dust to ignite, the resulting pressure and fireball should have been vented outside the building. However, the explosion vents on the baghouse faced the direction of adjacent storage silos (containing wood dust). When the explosion was vented out it ignited the storage silos resulting in a major portion of the fire.

Additionally, OSHA’s investigation showed that the baghouse lacked an explosion suppression system, was not designed and/or constructed to withstand the maximum unvented pressure of a combustible dust explosion, and in the absence of proper explosion protection, was located indoors.

As a result of these failures, when the reached the dust collector, the resulting explosion: blew the dust collector’s door off its hinges, creating a missile hazard, blew backwards into the duct, which burst open, and blew out the dust collector’s exhaust muffler and roof stack, causing the pressure/deflagration to be vented inside the building near responding firefighters.

NFPA 664 (2012) Requires an outdoor location for the dust collectors with fire or deflagration hazards, unless they are equipped with one of the following: (4) listed deflagration suppression system, (5) deflagration relief vents with relief pipes extending to safe areas outside the building and the collector meets the strength requirement of this standard (i.e. built with sufficient strength to withstand the maximum expected explosions pressure). NFPA 664 (2012) requires dust collectors with deflagration hazards be equipped with an appropriate-sized explosion suppression system and/or explosion relief venting system designed per NFPA 68 (Explosion Protection by Deflagration Venting) and NFPA 69 (Explosion Prevention Systems), and also that such dust collectors be built to design strength that exceeds the maximum expected explosion pressure of the material being collected. NFPA 69, 12.1.2 requires “Piping, ducts, and enclosures protected by an isolation system shall be designed to withstand estimated pressures as provided by the isolation system manufacturer”. NFPA 69, “System Verification” requires that systems shall be verified by appropriate testing under deflagration conditions to demonstrate performance.”

These design oversights directly increased the destructive power of what had until then been only a dust fire in the ductwork.

Lessons Learned From Wood Pellet Company Dust Explosion

Simply put, this disaster was bound to happen due to glaring design and/or construction flaws throughout the entire system.
The fact that multiple similar incidents have occurred at the facility demonstrates that the dust collection system, and perhaps even the entire production process requires modification to ensure this kind of incident does not occur again.

Under OSHA’s National Combustible Dust Emphasis Program, OSHA inspectors are on heightened alert for any combustible dust hazards in facilities in all industries. Indeed OSHA is under a federal mandate and its has as its own goal to issue a comprehensive combustible dust standard for general industry. In the meantime, OSHA has been citing plants under the general duty clause for having combustible dust hazards. In most cases, OSHA is informally requiring general industry to conform to the NFPA’s guidelines for combustible dust hazards. As seen in this case following they suggestions would have prevented this kind of incident from occurring.
Therefore, we can take away from this the need to be conscientious and proactive regarding combustible dust hazards in your facility. As we have seen, being reactive will simply not do.


* OSHA General Duty Clause (a) Each employer — (1) shall furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees; (2) shall comply with occupational safety and health standards promulgated under this Act.

*  Baghouse Explosion Vents – Explosion vents are a form of explosion protection used on baghouses. During normal operation the vents are closed and maintain an air-tight seal. However, if an explosion occurs within the baghouse, the vents are designed to “strategically fail” being the weakest part of the baghouse structure, thus allowing the pressure from the explosion to vent out and away from other combustible materials and workers.

About the Author: Samuel Dal Santo serves as Chairman of Samuel’s focus is on bringing about a reconciliation between often distant front office strategy, and field realities. Samuels unique background and field experience provides him with the needed experience, and real world skills that are often lacking in executive ranks today.

Wednesday, April 10, 2013

Combustible dust explosions cause injuries and deaths in the workplace

Combustible dust explosions cause injuries and deaths in the workplace

From EIN News and World News Report

Combustible dust explosions cause injuries and deaths in the workplace

Under certain conditions, combustible materials and materials that do not normally burn, can explode in dust form, causing serious injuries and wrongful deaths in the workplace.
March 20, 2013 /24-7PressRelease/ -- In the past six years, there have been over 50 combustible dust fires or explosions in the nation, causing nearly 170 injuries and more than 30 deaths. One explosion at a sugar refinery killed 14 workers and injured over 40 people. Such explosions and fires also cause extensive damage to industrial buildings and facilities each year.

Combustible dust

Under certain conditions, combustible materials -- and materials that do not normally burn -- can explode in dust form, causing serious injuries and wrongful deaths. A wide range of materials fall within this category and include the following industrial substances:

- Plant materials such as grain, tobacco, wood, paper and pulp
- Metals such as zinc, iron, aluminum, chromium and magnesium
- Foods such as those containing sugar, flour, spice or starch
- Fossil fuels
- Other items such as plastics, textiles, dyes, pesticides and pharmaceuticals

When the substances are reduced to dust form through the manufacturing process and hang in the air in specific concentrations, they create volatile circumstances that can lead to explosions. The conditions creating these deadly explosions and fires are highly controllable, meaning that companies have the capabilities to keep their workers safe. However, they are not required by law to do so.

New laws sought to create safe working environments

In an effort to create safer workplaces for industrial employees in the U.S., the federal legislature is revisiting a bill entitled the Worker Protection Against Combustible Dust Explosions and Fires Act. The bipartisan bill will force the Occupational Safety and Health Administration (OSHA) to establish interim protections for workers that prevent combustible dusts from accumulating.

OSHA creates and enforces guidelines for working conditions and safety measures for America's workers. Employers are obligated to provide safe working environments and safety devices for their employees. However, there are many instances of employers violating OSHA rules.

While some industries take steps to protect their employees from dust explosions, there is currently little federal regulation requiring them to do so. While OSHA has some protections in place, many claim that special interest groups and red tape are keeping the administration from enacting laws necessary for the protection of workers.

Although having new OSHA standards in place will not cure the problem, it will be a step in the right direction for people working around combustible dust particles.

Legal assistance for injured workers and surviving families

If you have suffered an injury in the workplace or elsewhere due to the negligence of an employer, business or individual, consult an experienced attorney. A lawyer knowledgeable about workers compensation claims and personal injury cases can help ensure that your rights are protected and that you obtain the compensation to which you are entitled.

Article provided by Huber & Palsir, LLC
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Hazard Communication Regulations

From Pallet Enterprise - Article - Safety Check: Hazard Communication Regulations

Safety Check: Hazard Communication Regulations
OSHA requires workers to be trained on new hazardous communication standards.

By DeAnna Stephens Baker
Date Posted: 4/1/2013

                Pallet companies that have not already begun training employees to understand the Occupational Safety and Health Administration’s (OSHA) new hazard communication (HazCom) standard should begin soon.

                HazCom is intended to ensure that anyone working around hazardous chemicals stay informed of potential risks and knows what to do if exposed. Last year, OSHA finalized new HazCom rules that incorporate the Globally Harmonized System of Classification and Labeling of Chemicals (GHS), a harmonized system used in Mexico, Europe, Asia, Australia and other countries. Under the new rule hazard warnings, material safety data sheets (MSDS) and labels, will have a standardized format. According to OSHA, the information required on the MSDS will remain essentially the same as that in the current standard. The main change will be the format requirements. Previously, there were no specific rules about what a chemical label or MSDS must look like. All employers are required to train any workers that could potentially be exposed to any hazardous chemicals on the new labels and MSDS requirements by Dec. 1, 2013.

                Though at first glance it may not seem like regulations regarding hazardous chemicals apply to pallet companies, most pallet companies deal with substances that are classified as hazardous in one way or another. Some hazardous chemicals that a pallet company might have on-site include gases, hydraulic fluids, equipment lubricants, greases and mold treatments. Therefore, many pallet plants are required to provide the required HazCom training to their employees. 

                Combustible dust is also an issue that wooden pallet companies need to pay attention to under HazCom since wood dust is considered combustible and some pallet companies have already received inspections as part of OSHA’s combustible dust national emphasis program. Because of the way wood dust is addressed in the new standard, it is likely to cause significant confusion for industry members. In the revised standard, OSHA has added it to the definition of hazardous chemicals, which means that combustible dust hazards must now be addressed on labels and MSDS. However, OSHA did not provide a definition for combustible dust due to ongoing rulemaking for it. Instead, the standard provides guidance on how to define combustible dust for the purposes of complying with HazCom by pointing to existing documents, such as OSHA’s Combustible Dust National Emphasis Program Directive (CPL 03-00-008) which includes an operative definition and provides information about current responsibilities in this area. It also recommends looking at voluntary industry consensus standards, particularly those of the National Fire Protection Association (NFPA), that address combustible dust. Pallet companies should keep up-to-date on what is happening regarding combustible dust as OSHA will likely be issuing more guidance as news rules are finalized.

                Any workers that could potentially be exposed to these or any other hazardous chemical must receive training on the new standards before the Dec. 1 deadline. In order to be in compliance with the training requirements, employers must fulfill certain obligations. Merely giving workers the MSDS to read is not enough. OSHA requires that the training be conducted as a forum that includes an explanation of both the hazards of the chemicals in the work area and how to use the information available as part of the company’s HazCom program. It can be in the form of classroom instruction, audiovisuals or an interactive video, but it should include a chance for employees to ask questions to make sure that they understand the information they are being given. As with all OSHA training requirements, the training must be given in a way that the workers can comprehend it. This means that if an employee receives job instructions in a language other than English, then the training and related information must also be conveyed in that language. Though employers are required to compile a list of all hazardous chemicals in their facilities, training does not need to be conducted on each specific chemical found. It can instead be conducted by categories of hazard (such as carcinogens, sensitizers or corrosive) that employees could encounter while working. 

                Employers should keep records of the training that takes place and which employees received it. OSHA may request this information at some point, and it is the only way to show you complied with training requirements. Training must take place as soon as a worker isassigned to work with a hazardous chemical. 

                There are many resources available to help conduct the required employee training both from OSHA as well as private companies. On its HazCom page (, OSHA has a number of resources available in both English and Spanish that can be used to assist with training. These include fact sheets, briefs and quickcards that discuss the training topics that employers must cover for the initial Dec. 1, 2013 deadline. OSHA’s website also has explanations of the new labeling elements and a step-by-step guide for employers to create a label that meets the requirements of the revised standard.

                For companies that do not wish to conduct the required training themselves, private companies offer a range of options in different formats, such as the online training available from MSDSonline ( or DVD and CD-roms available from J.J. Keller & Associates ( as well as many others. Whatever method of training that you choose, make sure that it includes all of the elements required by OSHA, as the employer is the one ultimately held responsible for meeting the requirements. 

                The training requirement is only the first part of the revised HazCom standard to go into effect. The rest of the standard will be phased in over the next several years. However, chemical manufacturers and importers can begin using new formats for labels and MSDS at any time during the transition period, emphasizing the need for training to be completed earlier rather than later. Other dates for employers to be aware of are:

                • June 1, 2015: OSHA will begin enforcing all the new provisions of the rule, and
                • June 1, 2016: By this time, employers must have updated labels as well as a written HazCom program.
                A complete timeline with more details and information on the training requirements are available on OSHA’s HazCom webpage.

Tuesday, April 9, 2013

Fire is Conveyable

Excellent article from Tom Andel at Material Handling and Logistics on conveyor fires.

Repeat After Me: "Fire is Conveyable" | Chain of Thought

Poor housekeeping and shoddy conveyor maintenance can ignite the dust accumulating in your workplace.

The safe, efficient flow of product through a facility demands that manufacturers separate conveyable from non-conveyable items. Unfortunately, some companies don’t realize that fire is very conveyable. New England Wood Pellet LLC learned that lesson recently after OSHA discovered that workers at two of the company’s plants were exposed to fire generated by the combination of combustible wood dust and a poorly conceived conveyor system.

The fact that a similar fire occurred at one of the company’s other plants told OSHA inspectors this was a problem of poor management practices, consequently the company could be facing a fine as high as $50,000. Their mistake was failing to isolate the conveying systems to prevent fire and rapid combustion from spreading both upstream and downstream in critical process equipment. In environments like theirs, wood dust, sources of combustion and poor ventilation can combine to create fire. Adding fuel to this one was the fact that this company’s process equipment lacked containment, explosion venting and suppression to mitigate the hazards of rapid and explosive combustion. Lack of spark detection and extinguishing systems in the wood pellet processing system completed the formula for disaster.
According to literature from Martin Engineering, the fact that conveyor belting itself can burn amplifies the consequences of a conveyor belt fire. The length and movement of the belt can spread a fire over a great distance within a facility in a very short time, this supplier warns.

“Fires on conveyor belting are most commonly ignited by the heat generated from friction induced by a pulley turning against a stalled (or slipping) belt or by the belt moving over a seized idler,” it adds. Best practices for minimizing the fire risk of any conveyor belt include:

∙ Conducting regular belt examinations;
∙ Removing all accumulations of combustible materials along the conveyor belt; and
∙ Correcting potential sources of fire such as seized rollers, overheated bearings, or belt misalignment.
I’m bringing this up because several landmark combustible dust accidents have made news in recent years (remember the Imperial Sugar explosion?) and earlier this year Rep. George Miller (D-CA) introduced H.R. 691, the Worker Protection Against Combustible Dust Explosions and Fires Act. This bill would require the Secretary of Labor to promulgate an interim final standard regulating occupational exposure to combustible dust hazards. It applies to “manufacturing, processing, blending, conveying, repackaging, and handling of combustible particulate solids and their dusts.”

The bill requires the management of such operations to:

∙ perform a hazard assessment identifying, evaluating, and controlling combustible dust hazards;
∙ have a written program that provides for hazardous dust inspection, testing, hot work, ignition control, and housekeeping;
∙ administer engineering controls, administrative controls, and operating procedures;
∙ implement good housekeeping to prevent accumulation of combustible dust in depths that can present explosion, deflagration, or other fire hazards; and
∙ provide safety and health information and annual training to managers and employees and their representatives.

Do conveyor fires happen very often? It’s hard to say how common they are because it’s the kind of incident that gets taken care of and goes unreported unless it turns into a catastrophe and gets OSHA attention. But the conditions are right for this happening anyplace that has old conveyors that haven’t been maintained regularly. That means poor lubrication, lousy bearings and lots of friction. And chances are, if conveyors aren’t maintained, housekeeping is probably also ignored—meaning significant dust accumulation. Those are the necessary ingredients for a conveyor fire.

But before shooting my blog off about this issue, I consulted my go-to expert on combustible dust to confirm it was worth bugging you about. That expert is John Astad, director and research analyst at the Combustible Dust Policy Institute in Santa Fe, Tex. I asked him what kinds of businesses could be kindling for a conveyor fire.

“Any business where equipment and materials can change, as well as your products’ dustiness, dryness or moisture content,” he said.
He cited the case of a sawmill in British Columbia that had originally been using green wood, but then started getting wood that was dried out and had a resin in it that increased its explosion severity. They didn’t recognize the fire hazard this represented.
But you don’t have to be in the wood industry to resemble the kind of company where change is part of life. What about third party logistics companies that take on new clients and new products with which they have little experience?

For such companies—and any company that regularly handles a variety of dust-prone products that might be new to them—Astad recommends they do a hazard assessment—a walkthrough of their facility to identify all potential heat sources.

“You have to look at all your potential combustibles and have a written plan on how to prevent any kind of combustible from being ignited,” he said. “These are issues that are already in the OSHA standard. You need a written hazard assessment plan for any kind of operation. Any time you have workers at a facility you need to do a hazard assessment. OSHA wants to see written work. They want proof that you did a walkaround and identified all hazards—including slip, trip and fall hazards.”

Astad admits to being confused about how OSHA communicates its guidelines about hazard assessments. You have to know where to look, and even he didn’t know that up to now you had to look under personal protective equipment, or PPE (1910.132(d)). So imagine his confusion about why this new standard introduced by Rep. Miller must also include a guideline on hazard assessment.

“When you write a bill I would think you do it for stuff that isn’t already there,” he said. “You and I already know about hazard assessment, that’s stuck over in PPE. And this other requirement for a written program that includes provisions for hazardous dust inspection, ignition control and housekeeping. That’s in the fire prevention plan (1910.39) that OSHA requires for ignition control. I guess this is job security for people in the beltway.”

Be that as it may, there are worse problems than legislation written in duplicate and triplicate that bombards you with too much information. One of those problems is the housing of a hazard that you know nothing about.

Monday, April 8, 2013

Preventing Wood Dust in the Plant

Preventing Wood Dust in the Plant

From our friend Jamison Scott, of Air Handling Systems

Preventing Wood Dust in the Plant

By Jamison Scott | 03/06/2013 12:26:00 PM 

One of the most important things a woodworking facility can do is engage in housekeeping and fugitive dust control. If underlying surface colors are not readily discernible on your equipment, there could be a dust deflagration hazard.

Do not ignore the wood dust. Clean it up, but do not blow it off with an air gun as that simply releases and stratifies the dust — use a vacuum to collect it. Then investigate to determine the source of the dust. For example, if the ductwork is not airtight, seal joints to prevent the release of dust. When inspecting the workplace for dust accumulations, consider all flat surfaces including rectangular-shaped ductwork, overhead beams, lighting fixtures and areas such as hung or suspended ceilings.

The National Fire Protection Assn., an International Codes and Standards Organization that creates voluntary consensus standards, provides guidelines for preventing combustible dust explosions. They include:

• NFPA 61: Standard for the Prevention of Fires and Dust Explosions in Agricultural and Food Processing Facilities. Current Edition: 2013
• NFPA 484: Standard for Combustible Metals, Current Edition: 2012
NFPA 654 Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids, Current Edition: 2013
• NFPA 655: Standard for Prevention of Sulfur Fires and Explosions, Current Edition: 2012
• NFPA 664: Standard for the Prevention of Fires and Explosions in Wood Processing and Woodworking Facilities, Current Edition: 2012
• And the proposed - NFPA 652: Standard on Combustible Dusts. With the first draft released last fall, this new standard will be a companion to the other combustible dust related standards. The development will take approximately three years with a proposed release date of Fall 2015.

Source: Jamison Scott is executive vice president of Air Handling Systems. With over 20 years of experience, he serves on the Technical Advisory Board for Air Pollution Control and Chairs the Industrial Dust Task Force for the WMMA. For information visit or call (203) 389-9595.

Click here to Jamison Scott's article on ComDust: What Woodworkers Need to Know

When is it Time to Examine Fire Safety Procedures? | Harrington Group, Inc.

When is it Time to Examine Fire Safety Procedures?
From Harrington Group, Inc.

When is it Time to Examine Fire Safety Procedures? 


Posted on Friday, April 5th, 2013
Flavors and Fragrance Explosion

On December 26, 2012, an explosion at a leading flavor and fragrance company, Givaudan Flavors Corp., shook nearby businesses and scattered debris throughout the plant grounds. Thankfully, no one was seriously injured. The explosion occurred in Florence, Kentucky when a silo was being filled by a semi-truck. That silo was heavily damaged and there was minor damage to the silo next to it, however, no other damages to the facility were noted.

This is the second time within a year that fire departments have responded to explosion reports at this manufacturing facility. The previous incident occurred in February 2012 when the same silo was being filled. News reports indicated that employees were filling the silo with chemicals when it over-pressurized and caused an explosion that again shook businesses nearby. One witness said that two or three times a year, he hears a big “boom” at the facility and then watches as fire departments arrive.

Givaudan Flavors, headquartered in Vernier, Switzerland, is a leading manufacturer in the fragrance and flavor industry. It operates in over 40 countries and employs more than 8,000 worldwide. Two incidents at the same facility within 10 months, in the same silo, begs the question, “When is it time to examine fire safety procedures?” Givaudan Flavors has been fortunate that in neither incident, no one was injured.

Serious fire or explosion incidents do happen, even at manufacturing facilities where accident prevention is taken seriously and incorporated well into daily plant life. Prevention efforts are never 100% fool-proof.  Serious fire or explosion incidents at any given facility are usually rare. When they do happen, it is critically important that a thorough and honest evaluation be conducted to identify the key contributing factors and extract as much learning from the failure as possible. But the evaluation is only half of it.  Corrective measures designed to neutralize the key contributing factors must actually be implemented, even if the expense is significant. Failure to do so will set the stage for a repeat of the same failure.

Sunday, April 7, 2013

OSHA Fines Plant Rocked By Dust Collection System Fire And Explosion on Environmental Expert

OSHA Fines Plant Rocked By Dust Collection System Fire And Explosion on Environmental Expert

OSHA Fines Plant Rocked By Dust Collection System Fire And Explosion

OSHA has issued huge fines over a combustible dust fire and explosion the tore through a wood pellet manufacturer’s dust collection system

May 14, 2012 | Jaffrey, NH -- OSHA fined the New England Wood Pellet, LLC a total of $147,000 over safety violations after a combustible dust fire and explosion rocked the company’s plant in Jaffrey, NH last week. The fines, which are some of the biggest yet this year, and the accompanying report on the incident that criticizes the company for failing to “effectively minimize and address clearly recognized hazards that could kill or disable workers in a catastrophic incident.”
The company for its part has fired back, saying OSHA’s findings are “one-sided and unfairly dismissive of the company's past and ongoing efforts to improve worker safety at its Jaffrey facility.”

The October 20, 2011 fire and explosion started when combustible wood pellet dust from the facility caught fire while in the plant’s dust conveyor system. After the fire started in the wood pellet cooler, the dust collection/conveyor system then transported the now burning dust throughout the system to equipment in other parts of the facility.  Once it reached the dust collector itself, the embers caused an explosion that then further spread the fire into storage silos that were located adjacent to the dust collector. The explosion also caused large amount of combustible dusts that had accumulated throughout the facility on overhead rafters and on other elevated places to catch fire.

Eventually, the fire became so large that it took more than 100 firefighters from 14 departments to control the blaze and took about 14 hours to extinguish.

The plant, which manufactures wood pellets by compressing wood dust, was previously cited by OSHA for a lack of properly installed and operated dust collection systems in the facility and for insufficiant housekeeping measures to control the accumulation of the combustible wood dust throughout the facility. For this reason, several of the citations from the October 20th incident were registered as “repeat serious offenses” that increased the fines considerably.

Specific Violations: Poor Dust Collection System Design, No Explosion Prevention/Protection

During its investigation OSHA found that a number of factors contributed to the severity of the incident. It found that the plant had failed to properly design and prepare their dust collection system for the fire and explosion hazards created by the combustible nature of the wood pellet dust. The report cited several instances where the dust collection/conveyor system, specifically the ductwork, pellet cooler, and the dust collector (baghouse) was either completely lacking any sort of fire suppression and explosion protection devices or were improperly installed.

Ductwork between various equipment located in different parts of the plant had no fire suppression devices (such as spark arrestors, ember suppression systems, etc.) to prevent sparks and embers from spreading throughout the system. This lead to a conflagration in the pellet cooler spreading through the ductwork to the dust collector in another part of the plant. Once in the dust collector, the fire lead to a dust explosion. While the dust collector did have explosion protection, it was not adequately sized, properly designed in that the explosion relief vents were positioned so as to vent the explosion back into the building towards workers in the area and out onto adjacent storage silos then subsequently caught fire.

The explosion also propagated back through the ductwork, which then burst open igniting large accumulations of dust on overhead rafters and other facility machinery.

OSHA also faulted the plant with failing to design and build ductwork and the dust collector to sufficient strength to withstand the maximum foreseeable explosion pressures from a potential combustible dust explosion. This lead to among other things, the door of the dust collector being blown off the collector, becoming a missile hazard.  Since the dust collector and ductwork were of inadequate strength to withstand a potential explosion, OSHA faulted the company for placing the dust collector inside the building.

Additionally, OSHA cited the plant for poor housekeeping efforts, failing to control the accumulation of the combustible wood pellet dust on overhead spaces such as rafters and large equipment. The company had a policy of cleaning dust accumulations using compressed air, in direct violation of OSHA regulations, for which is was fined previously. The large build up of combustible dust throughout the facility lead to secondary dust fires and explosions.*

In response to OSHA’s report, the company has defended itself, claiming it had taken all reasonable steps to ensure the safety of its workers. “Since 2008, New England Wood Pellet has worked cooperatively with [OSHA’s representatives], retained engineers and consultants, and spent over $2 million on various improvements to enhance worker safety at its Jaffrey facility” a statement from the company read.

They also took issue with comments from OSHA’s area director for New Hampshire, Rosemarie Ohar, and said they look forward to sharing their thoughts with OSHA regarding the citations. “We have a cooperative relationship with the New Hampshire OSHA office. This is the first time we'll get to share with them what we think since this citation was issued. We'll discuss the content of the citation and the amount of the penalties, and hopefully we can come to agreement there and continue to work together to make improvements in our plants, which we plan on doing anyway.”

Lesson For Others
Whether the company is successful in overturning or reducing the issued fines, this incident demonstrates the importance of proper dust collection system design in preventing combustible dust fires and explosions. Lack of effective planing and engineering in the system, as well as overlooking the seriousness of the threat combustible dusts pose lead to extensive damage to the plant, and large fines from OSHA.

While the company may be able to afford the fines, downtime from the resulting damage to the plant, and the now extensive repair costs will no doubt cost the company far more than remedying the problem in the beginning would have been.

About The Author:
Dominick DalSanto is an Author and Environmental Technologies Expert, specializing in dust collection systems. With nearly a decade of hands-on working experience in the industry, Dominick’s knowledge of the industry goes beyond a mere classroom education. He is currently serving as Marketing Director and Content Manager at His articles have been published not only on , but also on other industry related blogs and sites. In his spare time, Dominick writes about travel and life abroad for various travel sites and blogs. Follow Dominick on Google+

* A secondary dust fire/explosion occurs when an initial explosion causes a shockwave that then dislodges and disperses accumulations of dust often in elevated locations. The resulting dispersal of dust into the air many times leads to explosions of far great magnitude and destructive power than the initial conflagration. 

Additional Information About Combustible Dust Hazards:
Nine Years After Deadly Dust Explosion and Still No Comprehensive Dust Standard - CSB Director calls upon OSHA to finalize its long awaited combustible dust rule.

The Potential For Dust Explosions In Dust Collection Systems A guide to combustible dust hazards in general industry and how to minimize them.

Saturday, April 6, 2013

Spark Detection Saves Lives

Spark Detection Saves Lives : Engineering / Design

 Forest Product Industry:

 Dust Collector Fire

Spark Detection and Extinguishing Systems are your first line of defense in preventing fires and explosions in your process, conveying and dust collection systems.

Spark Detection and Extinguishment

For more information on fire and explosion protection find us at

For more information on combustible dust related issues check our blog at

Legislators, More Regulation is the ComDust Cure

More Regulation is the ComDust Cure?

From our friend John Astad at Combustible Dust Policy Institute.

Legislators, More Regulation is the ComDust Cure

Why is it that legislators seem to think that passing more bills and regulations is the cure all? Problem with the combustible dust issue is that no one in Washington D.C. has all the facts and solely utilizing the Chemical Safety Board's Dust Hazard Study provides a false perception of the enormity and complexity of the issues both social and economical.
"Their bill would tell OSHA to issue - within 90 days - an interim standard. It would require better housekeeping, engineering controls, worker training and a written combustible-dust safety program." article
For example, the CSB report states there were 281 ComDust incidents from 1980-2005, or an average of eleven incidents annually. In stark contrast, according to media accounts of ComDust related incidents since 2008 there have on an average 12 incidents a month. This would equate to approximately 4,000 ComDust incidents during the 1980-2005 timeframe.

Not understanding the depth of the issue is only part of the problem. For example FEMA/U.S. Fire Administration's, "National Fire Incident Reporting System 5.0 (NFIRS)" via local fire departments has failed to report and identify process situations, process conditions, and process materials regarding combustible dust related fires, precursors to catastrophic dust explosions.

If the local fire and explosions hazards can't be identified, then how can they be evaluated and controlled? Of course legislators at the national level seem to think legislation and regulation is the answer for a local/regional problem. That is the easy way out in attempting to solve a primarily fire life safety issue and secondarily an occupational safety issue.

The OSH ACT specifically states that to address workplace safety, issues of regulation, education, outreach, and research must be pursued. OSHA with its limited resources cannot do it all.
"by providing for research, information, education, and training in the field of occupational safety and health; and for other purposes."
What happened to NIOSH as the OSH ACT intended in getting involved with outreach/education regarding the combustible dust issue as it had done decades ago concerning coal mine dust explosions, prior to when the U.S Bureau of Mines (USBM) was transferred to NIOSH, Department of Energy (DOE), U.S. Geological Survey, and the Bureau of Land Management in 1995-97.

Let’s all grow up and stop singling out Imperial Sugar explosion as the problem. Currently Imperial Sugar is an industry leader in addressing ComDust fire and explosion hazards. What about the tens of thousands manufacturing facilities that have potential ComDust fire and explosion hazards? So now OSHA as Secretary of Labor states, "there's a new sheriff in town." So what we going to do, fine them all?

Outreach, training, research, and education through NIOSH and US Fire Administration are just a few examples in alternatives to more legislation and regulation. Question is, who has the vision in providing the leadership so all local, state, and federal agencies are working together in these tough economic times.

Resources -OSH Act

Combustible Dust NEP Status Report - October 2009

Here is the original OSHA Combustible Dust Status Report for your review.  It includes charts and graphs of the types of combustible dust industries and citations involved.

Combustible Dust NEP Status Report - October 2009


Combustible Dust Hazards
Office of General Industry Enforcement
Directorate of Enforcement Programs

October 2009



Fires and explosions fueled by combustible dusts have long been recognized as a major industrial hazard.  A November 2006, Chemical Safety Hazard Investigation Board (CSB) report described the occurrence of nearly 280 dust fires and explosions in U.S. industrial facilities over the past 25 years, resulting in approximately 119 fatalities and over 700 injuries.
OSHA initiated its Combustible Dust National Emphasis Program (NEP) on October 18, 2007, to inspect facilities that generate or handle combustible dusts that pose a deflagration/explosion or other fire hazard.  The NEP was based in large part on a Region III Special Emphasis Program that had begun in 2000.

Although OSHA, at present, does not have a specific standard on combustible dust hazards, there are several existing OSHA standards that apply to combustible dust handling facilities.  The NEP focuses on these standards, as well as the General Duty Clause.

Following a massive sugar dust explosion at Imperial Sugar's Port Wentworth Georgia facility on February 7, 2008, that killed 14 workers and injured many more, OSHA revised the Combustible Dust NEP to focus on industries with more frequent and high consequence dust incidents, and to include more inspections.  The revised NEP targets 64 types of industries.  In addition, all sugar refineries (beet and sugarcane) in Federal jurisdiction will be inspected.  OSHA also strongly recommended that all State Plans participate in the NEP.

Number and Types of Inspections Conducted under the NEP

The Combustible Dust National Emphasis Program applies to 64 industries (SICs / NAICs), including wood products, food products, metal products, chemicals, pharmaceuticals, rubber and plastic products, paper products, furniture, electric and sanitary services, transportation equipment, durable goods, and textile mills.  Each area office is required to conduct at least four inspections per year.  The figures below include inspections data from October 2007 through June 2009.   Since the inception of the NEP, more than 1000 inspections have been conducted, including inspections conducted by State Plan States.  (See Figure 1).  To date, 11 states have adopted OSHA's NEP and an additional four states have plans to adopt the program.

Total Number of Inspections Conducted
Figure 1
Figure 1. Number of Inspections Conducted

The wood products, food products, chemicals, metal products and rubber / plastic products industries account for more than 70 percent of inspections under the NEP.  See Figures 2 and 3 below for the types of industries inspected along with their numbers and percent distributions.
Figure 2
Figure 2. Types of Industries Inspected by Percent
Figure 3
Figure 3. Types of Industries Inspected by Number

Enforcement Findings

OSHA has found more than 4900 violations (See Figure 4) at the facilities inspected pursuant to the Combustible Dust NEP.  This includes not only combustible dust related violations, but also violations such as lockout/tagout, walking and working surfaces, and other hazards.

Total Number of Violations
Figure 4
Figure 4. Total Number of Violations

Percent Total VIolations Cited As Serious
Figure 5
Figure 5. Percent Total Violations Cited as Serious

Because hazards associated with combustible dust normally result in fires and/or explosions, the injuries would generally be burns, possibly resulting in death.  OSHA categorized 74 percent of violations found at the facilities under Federal jurisdiction as serious.  34 percent of violations in State Plan inspections were also characterized as serious (See Figure 5).

Violations Related to Combustible Dust Hazards

Under the NEP, the Hazard Communication standard is the standard most frequently cited with respect to combustible dust related hazards, followed by the housekeeping standard (see Figures 6 and 7).  OSHA's housekeeping standard at 29 C.F.R. 1910.22 not only applies to typical housekeeping hazards but also applies to dust accumulation hazards.  In several instances, OSHA found combustible dust accumulations ankle deep and covering an entire room.

Employers were also cited for violations of personal protective equipment, electrical equipment for hazardous (classified) locations, first aid, powered industrial trucks, and fire extinguisher standards during these inspections.  OSHA compliance officers also found that compressed air in excess of 30 psi was being used for cleaning purposes.  As well as violating an OSHA standard, the use of compressed air to clean accumulated dust would create a dust cloud and can result in deflagration or explosion if the ignition sources are present.  OSHA issued General Duty Clause citations for this practice (see Figure 6 and 7).

Combustible Dust Related Violations
Figure 6
Figure 6. Number of Combustible Dust Related Violations

Figure 7 shows that 20 percent of combustible dust related violations pertain to housekeeping, 27 percent to Hazard Communication, and 11 percent each to electrical, personal protective equipment, fire extinguishers and hazards addressed by the General Duty Clause.

Figure 7
Figure 7. Percent Combustible Dust Related Violation Distributions

In the absence of an OSHA standard, OSHA can cite Section 5(a)(1) of the OSH Act, the General Duty Clause, for serious hazards, such as fire and explosion hazards for which there are feasible means of abatement.  OSHA has referenced NFPA standards 654, 484, 61, and 664 as potential means of abating combustible dust hazards in citations issued under the NEP.  OSHA also referenced NFPA 499 in recommending safe practices for electrical equipment used in Class II locations, and NFPA 68 and 69 for explosion prevention and protection techniques.  Some of the hazards cited under the General Duty Clause are listed below.

Examples of General Duty Clause Violations

The following summarizes some General Duty Clause citations issued by OSHA under the Combustible Dust NEP:

  1. Dust collectors were located inside buildings without proper explosion protection systems, such as explosion venting or explosion suppression systems.
  2. Deflagration isolation systems were not provided to prevent deflagration propagation from dust handling equipment to other parts of the plant.
  3. The rooms with excessive dust accumulations were not equipped with explosion relief venting distributed over the exterior walls and roofs of the buildings.
  4. The horizontal surfaces such as beams, ledges and screw conveyors at elevated surfaces were not minimized to prevent accumulation of dust on surfaces.
  5. The ductwork for the dust collection system did not maintain a velocity of at least 4500 ft/min to ensure transport of both coarse and fine particles and to ensure re-entrainment.
  6. Flexible hoses used for transferring reground plastics were not conductive, bonded or grounded to minimize generation and accumulation of static electricity. A nonconductive PVC piping was used as ductwork.   Ductwork from the dust collection system to other areas of the plant was not constructed of metal.
  7. All components of dust collection system were not constructed of noncombustible materials in that cardboard boxes were being used as collection hoppers.
  8. Equipment such as grinders, shakers, mixers and ductwork were not maintained to minimize escape of dust into the surrounding work area.  Employer did not prevent the escape of dust from the packaging equipment, creating a dust cloud in the work area.
  9. Interior surfaces where dust accumulations could occur were not designed or constructed to facilitate cleaning and to minimize combustible dust accumulations.  Regular cleaning frequencies were not established for walls, floors, and horizontal surfaces such as ducts, pipes, hoods, ledges, beams, etc.
  10. Compressed air was periodically used to clean up the combustible dust accumulation in the presence of ignition sources.
  11. Air from dust collector was recycled through duct work back into the work area without the protection of a listed spark detection system, high speed abort gate and/or functioning extinguishing system.
  12. Air displaced during filling and emptying at the packaging and weighing systems which was discharged into the building was cleaned with a filter that was not 99.9 percent efficient at 10 microns.
  13. Exhaust ventilation systems were not installed to control dust clouds escaping from blending and other processing machinery.
  14. Bulk material conveyor belts were not equipped with bearing temperature, belt alignment, and vibration detection monitors at the head and tail pulleys to shut down equipment and/or notify the operator before the initiation of a fire and/or explosion.
  15. Enclosureless systems were allowed indoors where they were connected to sanders having mechanical feeds; where they were not emptied at least daily; where they were located in areas routinely occupied by personnel; and where they were not separated by at least 20 feet.
  16. Silos, legs of bucket elevators were not equipped with explosion relief venting.
  17. Explosion vents on dust collectors and bucket elevators were directed into work areas and not vented to a safe, outside location away from platforms, means of egress, or other potentially occupied areas.
  18. The dust collector's baghouse automatic pulse cleaning system was nonoperational due to equipment defects. The dust collector systems' hoods and ductwork were in disrepair with substantial air leaks in the ductwork created by missing inspection covers, unused opening, incomplete or poorly designed capture hoods and physical damage.
  19. A dust collector collecting aluminum dust was located inside a building and not located outside with appropriate venting and other safeguards to protect employees in the event of an explosion.
  20. Dust collectors were allowed to be shutdown periodically during unloading operations resulting in the creation of dust clouds in the processing areas. Procedures were not established to shut down related machinery if the dust collection system shuts down.
  21. Collection points used for manual cleanup of wood dust and other foreign material including metal were not provided with magnetic separators, grates or other types of screening to prevent foreign material from entering into the dust collection system.
  22. Automatic sprinkler systems were not provided on enclosureless dust collectors operating at 5500 cfm capacity, and were not separated by at least 20 feet from each other when located inside the buildings.
  23. Process Hazard Analysis was not conducted to determine whether the process hazards necessitated the installation of approved devices such as explosion protection systems, interlocked rotary valves, deflagration vents, and flame front diverters.
  24. Employees were exposed to explosion hazards due to the nitrogen blanketing piping disengaging from the mixer/blender during the mixing process.
  25. Mixers and blenders used for the production of pulverized collagen was not dust-tight and not equipped and provided with explosion prevention, relief and techniques.
  26. Miter saw was not maintained under continuous suction, thus allowing escape of dust during normal operation.
  27. The Coalpactors (hammer mills) used to crush coal and their connected feed chutes were not equipped with protective systems to prevent or mitigate a deflagration in the event of an ignition of combustible coal dust inside the Coalpactors.
  28. The company had not developed and implemented written Management of Change procedures for ensuring that potential changes to production equipment and dust control equipment do not result in fires, deflagrations and dust explosions.
  29. Screw conveyors or screw augers were not provided with deflagration isolation devices, such as, but not limited to, deflagration/explosion relief venting, containment, or isolation to prevent continued propagation flame front and over pressure into adjacent building/structures or equipment.
  30. The employer did not provided adequate maintenance and design of dust collector systems creating insufficient air aspirations, low duct velocities and blocked ducts.
  31. Propane burners with open flames were used in the area where agricultural products were ground.
  32. Employees were using electric grinder(s) on a duct entering a baghouse style dust collector without a hot work permit system.

OSHA found that the majority of facilities inspected under the NEP had dust collectors located inside the buildings without proper explosion protections systems, such as explosion vents or explosion suppression systems.

Average Number Violations Issued Per Inspection

The average number of violations per NEP inspection is 6.5 in Federal enforcement as compared to 3.1 for the other inspections (See Figure 8).  This means that OSHA is finding twice the number of violations at combustible dust handling facilities when compared to all other facilities in general.

Figure 8
Figure 8. Average Number of Violations per Inspection

Average Penalty per Serious Violation

The total citation penalty amount OSHA has proposed under the Combustible Dust NEP is:  $14,848,686.  However, OSHA proposed the third largest fine in its history, exceeding $8.7 million, following Imperial Sugar Refinery explosion in February 2008.  The average penalty proposed per serious violation during combustible dust NEP inspections is $1233 for Federal OSHA, and $791 for State Plans.

Figure 9
Figure 9. Average Penalty per Serious Violation

Percent Inspections In-Compliance

OSHA found during the inspection of combustible dust handling facilities that only 18 to 22 % of facilities inspected were found to be in compliance with OSHA requirements (see Figure 10).  OSHA's goal is that 100 percent of these inspections find compliance with OSHA requirements.

Figure 10
Figure 10. Percent Inspections In-Compliance

Combustible Dust Hazards Training

OSHA has included combustible dust hazards in the Process Safety Management course it provides its compliance officers for more than three years.  Over 350 compliance officers have received the PSM segment of training on combustible dust hazards.  In addition, OTI, OSHA's Training Institute, has developed a specialized comprehensive three and one-half day course on Combustible Dust Hazards and Controls, which it began conducting since December 2007.  Since the inception of this course, more than 200 Federal and state OSHA personnel have successfully completed it, and more classes are scheduled.  OTI has also conducted two refresher seminars for nearly 1,400 Federal and State Plan personnel across the nation.  Training is limited to OSHA and State personnel.

Combustible Dust Hazards Outreach

In 2005, OSHA issued a Safety and Health Information Bulletin entitled Combustible Dust in Industry:  Preventing and Mitigating the Effects of Fire and Explosions.  This comprehensive guidance highlights the hazards associated with combustible dusts, the work practices and engineering controls that reduce the potential for a dust explosion or that reduce the danger to employees if such an explosion should occur, and the training needed to protect employees from these hazards.  In March 2008, OSHA mailed copies of this guidance to 30,000 employers in industries it identified as being an at-risk for dust hazards, a proactive step to remind employers of their duty to furnish their employees with places of employment that are free of hazards and to provide them with instruction and information as to how this can be accomplished.

OSHA is providing other assistance to employers and employees to protect against combustible dust hazards. Specifically, OSHA has created:

  • a website, specifically dedicated to combustible dust hazards,
  • a safety alert, and
  • a poster addressing the measures employers handling combustible dusts must take.

OSHA is taking, and will continue to take, strong enforcement actions to address combustible dust hazards.  The Agency's strong enforcement of applicable regulatory and statutory requirements combined with education and outreach to employers and employees is helping to protect the safety and health of working men and women who may be exposed to combustible dust hazards.  However, OSHA recognized that there are limitations to this approach, and OSHA has also initiated rulemaking to provide more targeted tools to address combustible dust hazards.