Tuesday, April 29, 2014

Classification of cumbustible dust under Ammended 29 CFR 1910.1200 Hazcom

December 27, 2013
THROUGH: Dorothy Dougherty
Acting Deputy Assistant Secretary
FROM: Thomas Galassi, Director
Directorate of Enforcement Programs
SUBJECT: Classification of Combustible Dusts under the Revised Hazard Communication Standard 
This memorandum provides guidance for compliance safety and health officers (CSHOs) to use in determining whether manufacturers or importers have properly classified their products1 for combustible dust hazards under the revised Hazard Communication Standard (HCS). This guidance shall be used when inspecting manufacturers and importers, usually from referrals concerning inadequate or inappropriate labels or SDSs are conducted, not inspections of downstream users. Until OSHA addresses these issues through rulemaking, CSHOs shall use this document to determine if manufacturers and importers (from now on "classifier") are in compliance with the obligations of 1910.1200(d) for combustible dust. CSHOs may direct any questions that arise in applying this guidance to the Directorate of Enforcement Programs or the Salt Lake Technical Center (SLTC). 


On March 26, 2012, OSHA amended the HCS to align with the Globally Harmonized System for the Classification and Labelling of Chemicals (GHS). However, the GHS does not contain a classification for combustible dust hazards, and to maintain coverage of this hazard under the HCS, OSHA amended the standard's definition of "hazardous chemical" to include "combustible dust2 ." Noting ongoing efforts at the United Nations (UN) and in the Agency's own combustible dust rulemaking, OSHA did not adopt a definition of the term combustible dust in the final rule. Rather, as an interim measure, OSHA stated that it had already provided guidance on combustible dust, including the Combustible Dust National Emphasis Program (NEP), which "includes an operative definition." 77 FR 17705. OSHA also noted that a number of voluntary consensus standards exist, "particularly those of the NFPA," which provide further guidance. Id.

Compliance Guidance

Under the HCS, classifiers are required to "evaluate chemicals produced in their workplaces or imported by them to classify the chemicals in accordance with this section." 29 CFR 1910.1200(d)(1). Any such classification must "identify and consider the full range of available scientific literature and other evidence concerning the potential hazards." 1910.1200(d)(2). However, there "is no requirement to test the chemical to determine how to classify its hazards." Id. The classifier must consider not only the hazards of the chemical in the form it is shipped, but also consider the hazards that arise under normal conditions of use and foreseeable emergencies. When performing inspections of classifiers, CSHOs must ensure that the requirement to consider normal conditions of use and foreseeable emergencies is followed by the classifier.
The combustible dust NEP defines combustible dust as a solid combustible material, composed of distinct pieces or particles, that "presents a fire or deflagration hazard when suspended in air or some other oxidizing medium over a range of concentrations, regardless of particle size or shape." A number of voluntary standards prepared by the National Fire Protection Association (NFPA), FM-Global, and ASTM International suggest various tests, data, and criteria that may be used to determine whether a material presents a combustible dust hazard.
As noted above, classifiers must consider any hazards posed by the product in normal conditions of use and foreseeable emergencies, and must consider the full range of available information about those hazards. For combustible dusts, often the best information is actual experience with the product. If the classifier knows that its product has been involved in a deflagration or dust explosion event, the classifier should classify the product as a combustible dust unless the classifier can show that the conditions surrounding the event are not expected in normal conditions of use or foreseeable emergencies. In the absence of information on a deflagration or dust explosion event, classifiers may use one or more of the following approaches in determining whether such hazards exist, depending on the information that is available.
  1. Laboratory Testing.

    All of the voluntary standards recognize that reliable test data for a material, based on scientifically validated tests, is strong evidence for determining whether a material presents a combustible dust hazard and should be used for classification if available. Reliable screening tests, such as that described in ASTM E12263 , showing a positive normalized rate of pressure rise (Kst), and tests for Class II dusts may be used to determine whether a material presents a combustible dust hazard, and classification should be based on such data if it is available. Many voluntary standards recognize the ASTM E1226 and E15154 methods as reliable means to establish a combustible dust hazard. When performing inspections of classifiers CSHOs must obtain and evaluate any appropriate and available test results for the product to ensure the classification accurately reflects the hazards of the chemical.

    OSHA's combustible dust NEP describes its own test method for determining the Kst, and the NEP treats a dust as presenting the hazard when the Kst is greater than zero. In addition, the NEP describes OSHA's method for determining whether a dust is a Class II dust for purposes of the electrical standard, which is also an indication that a dust presents a combustible dust hazard. If laboratory data (e.g., company-generated data or regulatory body test results for the product) are available and the classifier chooses not to classify based on this data, the CSHO must ensure that classifier can adequately explain why this data was not used in the classification.
  2. Published Test Results.

    NFPA 615 , 686 , 4847 , and 4998 publish lists of test results for various materials. Though the NFPA documents caution care in the use of these results because the extent of explosibility can vary even for different dusts of the same solid material, they nonetheless can "aid in the determination of the potential for a dust hazard to be present in [an] enclosure." NFPA 61, A.6.2.1 (2013).

    As a part of a poster about combustible dust hazards, OSHA has published a list of combustible materials based on the information provided in the NFPA standards (https://www.osha.gov/Publications/combustibledustposter.pdf). In addition, there are public databases of dust explosibility characteristics that may be consulted, such as the "Gestis-Dust-EX" database maintained by the Institute for Occupational Safety and Health of the German Social Accident Insurance (http://www.dguv.de/ifa/en/gestis/expl/index.jsp).

    In the absence of any test data for a particular product, the classifier may rely on published test data for the classification of dusts if the data is for a material that is substantially similar to the product under review. Where the classifier has not classified its product as presenting a combustible dust hazard and the CSHO finds positive published data for a material that appears similar, the CSHO must ensure that the classifier has an adequate explanation for discounting the data.
  3. Dust Particle Size.

    For many years, NFPA 6549 defined combustible dust as a "finely divided solid material 420 microns or smaller in diameter (material passing a U.S. No. 40 Standard Sieve) that presents a fire or explosion hazard when dispersed and ignited in air." OSHA used this definition in earlier combustible dust guidance, such as its 2005 safety and health information bulletin, and uses a similar criterion in defining "fugitive grain dust" in its Grain Handling Facilities Standard (see 29 CFR 1910.272(c)). Some NFPA standards still use a size criterion in defining combustible dust, such as NFPA 61 (2013) and NFPA 704 (2012)10 .

    Other NFPA standards, however, have changed their combustible dust definition to remove the size criterion, but discuss size in their explanatory notes. In general the notes concerning particle size state that dusts of combustible material with a particle size of less than 420 microns can be presumed to be combustible dusts. However, certain particles, such as fibers, flakes, and agglomerations of smaller particles, may not pass a No. 40 sieve but still have a surface-area-to-volume ratio sufficient to pose a deflagration hazard. In the most recent revisions, the explanatory notes in many of the NFPA standards have moved from a 420 to 500 micron size threshold. See NFPA 484 (2013), NFPA 654 (2013), NFPA 66411 (2012) and FM Global Data Sheet 7-76 (2013)12 .

    Where there is no test data, or if the testing is inconclusive, classification may be based on particle size, if particle size information is available. If the material will burn and contains a sufficient concentration of particles 420 microns or smaller to create a fire or deflagration hazard, it should be classified as a combustible dust. A classifier may, if desired, instead use the 500 micron particle size (U.S. Sieve No. 35) threshold contained in more recent NFPA standards. Care must be used with this approach where the particles are fibers or flakes, or where agglomerations of smaller particles may be held together by static charges or by other means that would prevent the dust from passing through respective sieves No. 40 and 35, but would still present a fire or deflagration hazard.


In summary, when conducting inspections of classifiers, CSHOs should determine how classifiers have handled the available evidence about a product's explosibility. Where there is evidence that the product has actually been involved in a deflagration or dust explosion event, it should be classified as a combustible dust. Similarly, where results of accepted tests on the product are available, the dust should be classified in accordance with those results. Finally, in the absence of actual events or test data on the product, the classifier may either rely on the published test data on similar materials or use the available information about particle size to determine the combustible dust hazard of the product.
This guidance is not intended to be exclusive, and classifiers may have other reliable methods to establish whether their product does or does not present a combustible dust hazard in normal conditions of use and foreseeable emergencies. CSHOs should consider such claims carefully, and in such cases consultation with the Directorate of Enforcement Programs and/or the SLTC is strongly encouraged.

Wednesday, April 23, 2014

Hazard Communication Final Rule

New changes to the Occupational Safety and Health Administration's (OSHA) Hazard Communication Standard are bringing the United States into alignment with the Globally Harmonized System of Classification and Labeling of Chemicals (GHS), further improving safety and health protections for America's workers. Building on the success of OSHA's current Hazard Communication Standard, the GHS is expected to prevent injuries and illnesses, save lives and improve trade conditions for chemical manufacturers. The Hazard Communication Standard in 1983 gave the workers the ‘right to know,' but the new Globally Harmonized System gives workers the ‘right to understand.'

The new hazard communication standard still requires chemical manufacturers and importers to evaluate the chemicals they produce or import and provide hazard information to employers and workers by putting labels on containers and preparing safety data sheets. However, the old standard allowed chemical manufacturers and importers to convey hazard information on labels and material safety data sheets in whatever format they chose. The modified standard provides a single set of harmonized criteria for classifying chemicals according to their health and physical hazards and specifies hazard communication elements for labeling and safety data sheets. 

Benefits: The new standard covers over 43 million workers who produce or handle hazardous chemicals in more than five million workplaces across the country. The modification is expected to prevent over 500 workplace injuries and illnesses and 43 fatalities annually. Once fully implemented it will also:
  • Improve the quality and consistency of hazard information in the workplace, making it safer for workers to do their jobs and easier for employers to stay competitive;
  • Enhance worker comprehension of hazards, especially for low and limited-literacy workers, reduce confusion in the workplace, facilitate safety training, and result in safer handling and use of chemicals;
  • Provide workers quicker and more efficient access to information on the safety data sheets;
  • Result in cost savings to American businesses of more than $475 million in productivity improvements, fewer safety data sheet and label updates and simpler new hazard communication training: and
  • Reduce trade barriers by harmonizing with systems around the world.
Rulemaking background: OSHA published a Notice of Proposed Rulemaking to update the Hazard Communication Standard in September 2009 and held public hearings in March 2010.
Major changes to the Hazard Communication Standard:
  • Hazard classification: Chemical manufacturers and importers are required to determine the hazards of the chemicals they produce or import. Hazard classification under the new, updated standard provides specific criteria to address health and physical hazards as well as classification of chemical mixtures.
  • Labels: Chemical manufacturers and importers must provide a label that includes a signal word, pictogram, hazard statement, and precautionary statement for each hazard class and category.
  • Safety Data Sheets: The new format requires 16 specific sections, ensuring consistency in presentation of important protection information.
  • Information and training: To facilitate understanding of the new system, the new standard requires that workers be trained by December 1, 2013 on the new label elements and safety data sheet format, in addition to the current training requirements.
Changes from the Proposed to the Final Rule: OSHA reviewed the record and revised the Final Rule in response to the comments submitted. Major changes include:
  • Maintaining the disclosure of exposure limits (Threshold Limit Values [TLVs]) established by the American Conference of Governmental Industrial
  • Hygienists (ACGIH) and carcinogen status from nationally and internationally recognized lists of carcinogens on the safety data sheets;
  • Clarification that the borders of pictograms must be red on the label;
  • Flexibility regarding the required precautionary and hazard statements to allow label preparers to consolidate and/or eliminate inappropriate or redundant statements; and
  • Longer deadlines for full implementation of the standard (see the chart below):
What you need to do and when:
  • Chemical users: Continue to update safety data sheets when new ones become available, provide training on the new label elements and update hazard communication programs if new hazards are identified.
  • Chemical Producers: Review hazard information for all chemicals produced or imported, classify chemicals according to the new classification criteria, and update labels and safety data sheets.
Effective Completion Date Requirement(s) Who
December 1, 2013 Train employees on the new label elements and SDS format. Employers
June 1, 2015*

December 1, 2015
Comply with all modified provisions of this final rule, except:

Distributors may ship products labeled by manufacturers under the old system until December 1, 2015.
Chemical manufacturers, importers, distributors and employers
June 1, 2016 Update alternative workplace labeling and hazard communication program as necessary, and provide additional employee training for newly identified physical or health hazards. Employers
Transition Period Comply with either 29 CFR 1910.1200 (this final standard), or the current standard, or both. All chemical manufacturers, importers, distributors and employers
* This date coincides with the European Union implementation date for classification of mixtures.
Other U.S. Agencies: The Department of Transportation (DOT), Environmental Protection Agency, and the Consumer Product Safety Commission actively participated in developing the GHS. DOT has already modified its requirements for classification and labeling to make them consistent with United Nations transport requirements and the new globally harmonized system. 

Global implementation: The new system is being implemented throughout the world by countries including Canada, the European Union, China, Australia, and Japan.

Additional information: More information on the hazard communication standard, including the link to the Federal Register notice, can be found on OSHA's hazard communication safety and health topics page at www.osha.gov/dsg/hazcom/index.html.

Friday, April 18, 2014

Basics of Substitution & Alternatives Assessment

BasicsConsidering safer alternatives to hazardous chemicals is not a new approach. Thinking about safer alternatives allows employers, workers, and decision-makers to identify solutions, rather than continuing to evaluate and quantify the problem. This approach can reduce costs and keep businesses competitive. On the other hand, continuing to assess a problem has no economic benefit.

Several terms and phrases are commonly used to describe this type of solutions-oriented approach to chemical management.
Informed substitution, replacing hazardous substances with safer alternatives, is the goal of a solutions-oriented approach to chemical management. It involves identifying alternatives and evaluating their health and safety hazards, potential trade-offs, and technical and economic feasibility. A safer alternative is an option that is less hazardous for workers than the existing means of meeting that need. Sometimes, this means choosing the option of not continuing an activity altogether; this also may include using chemical substitutes or product or process redesigns that completely eliminate the need for specific hazardous chemicals. Informed substitution is the goal of the seven step process presented by OSHA in this toolkit.
Substitution planning is a process to systematically set goals and priorities to reduce hazards, develop a chemical use inventory, evaluate alternatives, identify preferred alternatives, and implement alternatives. Taken together, steps 1-7 outline a substitution planning process.
An alternatives assessment is a process for identifying, comparing, and selecting safer alternatives for hazardous chemicals on the basis of their hazards, performance, and economic viability. An alternatives assessment is a key component of a substitution planning process and is used in the evaluation and comparison of alternatives.
A number of tools and methods have been developed to evaluate hazards, performance, and economic viability as part of an alternatives assessment. For example, comparative chemical hazard assessment tools provide a method to compare chemical alternatives on the basis of their chemical hazards. Steps 3-5 of the toolkit – identifying, assessing, comparing, and selecting the alternatives – include tools employers and workers can use to perform an alternatives assessment.

Further Resources


  • Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ). Practical Chemical Management Toolkit. This toolkit provides a step-by-step process for identifying and assessing chemical hazards, managing the risks associated with the use of chemicals, and planning and preparing for any emergencies involving chemicals.
  • Interstate Chemicals Clearinghouse (IC2). IC2 Safer Alternatives Assessments. This website outlines a protocol for conducting safer alternatives assessments and provides a set of resources to draw from when performing an alternatives assessment.
  • Ontario Toxics Reduction Program. Reference Tool for Assessing Safer Chemical Alternatives. This reference tool provides support and guidance for government, industry, and other stakeholders to identify and consider safer alternatives.


  • BizNGO. BizNGO Chemical Alternatives Assessment Protocol. *(PDF) This resource is a decision framework for substituting chemicals of concern to human health or the environment with safer alternatives.
  • BizNGO. The Guide to Safer Chemicals. This resource is a hands-on guide for downstream users of chemicals that charts pathways to safer chemicals in products and supply chains.
  • Chemical Commons. Principles for Alternatives Assessment. This framework includes six principles for alternatives assessment that guide a process for well-informed decision making that supports successful phase-out of hazardous products, phase-in of safer substitutes, and elimination of hazardous chemicals where possible.
  • European Commission. Minimizing Chemical Risk to Workers' Health and Safety Through Substitution. This report presents a systematic, yet flexible, risk-based process for chemical substitution in the workplace.
  • German Federal Environment Agency (Umweltbundesamt). Guide on Sustainable Chemicals. This guide assists in the selection of sustainable chemicals by providing criteria to distinguish between sustainable and non-sustainable substances.
  • German Federal Institute for Occupational Safety and Health (BAuA). Technical Rules for Hazardous Substances—Substitution (TRGS 600). This guidance provides a framework for identifying and evaluating substitutes and establishes criteria for assessing and comparing the health risks, physicochemical risk, and technical suitability of identified alternatives.
  • Interstate Chemicals Clearinghouse (IC2). Guidance for Alternatives Assessment and Risk Reduction. This document provides background information on what is found in and how to conduct an alternatives assessment.
  • Lowell Center for Sustainable Production. Alternatives Assessment Framework. This resource provides a framework for the quick assessment of safer and more socially just alternatives to chemicals, materials, and products of concern.
  • National Institute for Occupational Safety and Health. Prevention through Design (PtD). This website describes the concept of Prevention through Design, a framework for addressing occupational safety and health needs in the design process to prevent or minimize the work-related hazards and risks associated with the construction, manufacture, use, maintenance, and disposal of facilities, materials, and equipment.
  • U.S. EPA Design for the Environment Program. Alternatives Assessments. This website describes the key steps to conducting an alternatives assessment.
  • U.S. EPA. Greening Your Purchase of Cleaning Products: A Guide for Federal Purchasers. This website highlights guiding principles that provide a framework purchasers can use to make environmentally preferable purchases.


  • Massachusetts Toxics Use Reduction Institute. Five Chemical Alternatives Assessment Study. This study presents a methodology for assessing alternatives to chemical of concern based on performance, technical, financial, environmental, and human health parameters.
  • U.S. EPA Design for the Environment Program. Cleaner Technologies Substitutes Assessments. This publication presents the methods and resources needed to conduct a Cleaner Technologies Substitutes Assessment (CTSA), a methodology for evaluating the comparative risk, performance, cost, and resource conservation of alternatives to chemicals currently used by specific industry sectors.

Monday, April 14, 2014

Why transition to safer chemicals?

 Transitions Pyramid 
It is widely recognized that the most effective method to eliminate or reduce adverse health and safety outcomes in the workplace is to eliminate hazards at the source, before applying other, less effective forms of protection. This industrial hygiene principle, known as the hierarchy of controls, has been well-studied, widely accepted and prominently incorporated into practice by businesses and industrial hygiene professionals throughout the world.

In chemical management, this hierarchy guides employers and workers to eliminate or reduce hazardous chemicals at the source by substituting them with safer alternatives. Unlike traditional engineering controls, administrative controls, work practice controls, or personal protective equipment, these strategies can completely eliminate exposure to hazardous chemicals, reduce the potential for chemical accidents, reduce disposal costs, and remove concerns regarding worker compliance and equipment maintenance.
Eliminating or reducing chemical hazards at the source, when coupled with a thoughtful, systematic evaluation of alternatives and the adoption of safer chemicals, materials, products and processes, can provide substantial benefits to both workers and businesses.

Improve worker health and safety: In the United States, it is estimated that chemicals are the cause of more than 190,000 illnesses and 50,000 deaths suffered annually by workers.1 These numbers are likely an underestimate due to long latency periods between chemical exposures and the onset of disease, unrecognized relationships between illnesses and chemicals, and other factors. Replacing known hazardous chemicals with safer alternatives could help reduce these numbers.

Reduce costs: Using hazardous chemicals in the workplace results in substantial direct, indirect, and liability costs to businesses and society.2 Step 4 of the toolkit outlines these in detail. Transitioning to safer alternatives can reduce these costs, as well as improve other important measures of success, such as performance efficiency, industry leadership and corporate stewardship. A 2008 study by the American Industrial Hygiene Association demonstrated that making process improvements designed to reduce or eliminate workers’ exposures to hazardous chemicals resulted in greater savings and other benefits than implementing controls further down the hierarchy (i.e., engineering controls, administrative and work practice controls, and PPE).3

Reduce potential for regrettable substitutions: Hazardous chemicals have the potential to be replaced with substitute chemicals or redesigned products or processes that may pose new and potentially greater hazards to workers. Implementing a process of informed substitution – which examines the hazard, performance, and cost of all options – can protect workers and identify replacements that are unlikely to cause more problems or be a target of future regulatory efforts.

Achieve compliance with laws and regulations: Although federal, state, and local legislation in the U.S. has been in place for many years to regulate chemicals (e.g., OSHA’s Occupational Safety and Health Act of 1970, EPA’s Toxic Substances Control Act of 1976), in recent years new international, federal, and state regulations are now requiring manufacturers, importers, and distributors to disclose more information about chemicals throughout the supply chain (e.g., REACH), avoid certain chemicals (e.g., Restriction of Hazardous Substances Directive (RoHS), Maine Kids Safer Products Law), and implement safer chemicals where feasible (e.g., EU Chemical Agents Directive, EU Carcinogens and Mutagens Directive). Additional laws and regulations restricting hazardous chemical use or emissions are also on the horizon. The cost of not complying with existing laws or preparing for future efforts can be substantial. For example, as a result of a European Union law restricting certain chemicals in electronics, 29% of 200 U.S. firms surveyed incurred lost or delayed sales into the European Union costing an average of nearly $2 million per firm.4 Taking a proactive approach by transitioning to safer alternatives can not only help businesses remain compliant with laws and regulations, but also remain competitive in a global marketplace.

Create safer products for consumers and the environment: Transitioning to safer chemicals in the workplace can also contribute to creating products that are less hazardous for consumers and for the environment. This gives businesses the opportunity to brand their company with a new, green and innovative image.

1 This number is derived using the methodology from “Green Chemistry in California: A Framework for Leadership in Chemicals Policy and Innovation,” (http://coeh.berkeley.edu/docs/news/06_wilson_policy.pdf *(PDF)) to estimate illness and deaths attributable to workplace chemical exposures.
2 For more information about the costs associated with workplace injuries and illnesses, see OSHA’s Safety and Health Topics Page on the Business Case for Safety and Health: https://www.osha.gov/dcsp/products/topics/businesscase/
3 American Industrial Hygiene Association. (2008). Demonstrating the business value of industrial hygiene: Methods and findings from the value of the industrial hygiene profession study. Retrieved from: http://www.aiha.org/votp_new/pdf/votp_report.pdf *(PDF)
4 University of Massachusetts, Lowell. (2010). CLEAN TECH: An agenda for a healthy economy. Retrieved from: http://www.sustainableproduction.org/downloads/CleanTechLongFinal2-10_000.pdf *(PDF)