Qualitative Risk Characterization and Management of Occupational Hazards: Control Banding (CB) A Literature Review and Critical Analysis DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention National Institute for Occupational Safety and Health Disclaimer Mention of any company or product does not constitute endorsement by the National Institute for Occupational Safety and Health (NIOSH). In addition, citations to Web sites external to NIOSH do not constitute NIOSH endorsement of the sponsoring organizations or their programs or products. Furthermore, NIOSH is not responsible for the content of these Web sites. Ordering Information To receive documents or other information about occupational safety and health topics, contact NIOSH at Telephone: 1–800–CDC–INFO (1–800–232–4636) TTY: 1–888–232–6348 E-mail: [email protected] or visit the NIOSH Web site at www.cdc.gov/niosh. For a monthly update on news at NIOSH, subscribe to NIOSH eNews by visiting www.cdc.gov/niosh/eNews. DHHS (NIOSH) Publication No. 2009–152 August 2009 SAFER • HEALTHIER • PEOPLE™ ii FOREWORD When the U.S. Congress passed the Occupational Safety and Health Act of 1970 (Public Law 91–596), it established the National Institute for Occupational Safety and Health (NIOSH). Through the Act, Congress charged NIOSH with recommending occupational safety and health standards and describing exposure levels that are safe for various periods of employment, including but not limited to the exposures at which no worker will suffer diminished health, functional capacity, or life expectancy as a result of his or her work experience. NIOSH communicates recommended standards to regulatory agencies (including the Occupational Safety and Health Administration [OSHA]), health professionals in academic institutions, industry, organized labor, public interest groups, and others in the occupational safety and health community through criteria documents. Yet limited resources, incomplete data, and the ever-expanding inventory of chemical hazards in the workplace and global commerce make it infeasible to develop standards for all possible hazards. Consequently, NIOSH has also been tasked with assessing and providing technical solutions and promising intervention strategies to protect the safety and health of workers. One such emerging strategy has gained increasing attention among safety and health practitioners: a qualitative risk characterization and management strategy, also referred to as control banding (CB). This strategy groups workplace risks into control bands based on evaluations of hazard and exposure information. The utility of CB is recognized by a number of international organizations, and widening interest can be gauged by the growing literature describing qualitative risk assessment and management strategies. Despite limitations, in the absence of recommended standards, CB may be a useful strategy for assessing and controlling occupational hazards as part of a comprehensive safety and health program. This document is generated from literature reviews of recent developments describing such exposure-characterization and risk-management strategies in occupational settings. In particular, this document summarizes the literature describing qualitative risk assessment and strategies of risk management. The intent of this review is to provide a broad description of qualitative strategies to reduce risk of exposure to occupational hazards, recognizing that a deliberate and extensive review of the literature on this topic will help guide decisions for where CB applications may be most effective. Also important is finding where limitations in our understanding may require additional research or modification or may preclude the use of CB strategies altogether. In meeting these objectives, this document intends to inform its audience—mostly occupational safety and health practitioners, researchers, policy and decision makers, employers, and iii workers in potentially hazardous work places—of the concepts of CB and the promise it holds as a tool for use within a broader comprehensive occupational safety and health program. Christine M. Branche, Ph.D. Acting Director, National Institute for Occupational Safety and Health Centers for Disease Control and Prevention iv EXECUTIVE SUMMARY The majority of chemical substances in commerce have no established occupational exposure limits (OELs). In the absence of established OELs, employers and workers often lack the necessary guidance on the extent to which occupational exposures should be controlled. A strategy to control occupational exposures that may have value when there are no relevant OELs is known as control banding (CB). CB is a qualitative strategy for assessing and managing hazards associated with chemical exposures in the workplace. The question about the utility of the CB strategy for workplaces in the United States has been raised, warranting a critical review of its concepts and applications. This report is the result of a review of the published literature and related proceedings on CB. The conceptual basis for CB is the grouping of chemical exposures according to similar physical and chemical characteristics, intended processes/handling, and anticipated exposure scenarios (amount of chemical used and how workers would be exposed). Based on these factors, appropriate control strategies (that is, risk management options) are determined for each of these groupings. In one of the least complex forms, a four-level hierarchy of risk management options for controlling exposures to chemicals includes— 1. good occupational hygiene practices, which may be supplemented by use of appropriate personal protective equipment (PPE) 2. engineering controls, including local exhaust ventilation (LEV) 3. containment 4. seeking specialist advice To determine the appropriate control strategy, one must consider the characteristics of a particular chemical substance and the potential for exposure (based on quantity in use, volatility [for liquids], or dustiness [for solids], and the relative hazard as described in what is known as a risk phrase, or R-phrase). Determining potential exposures for airborne particulates or vapors involves characterizing the process or activity in which the chemical substance is used. Work processes help in assigning the chemical substance to a CB. These CBs provide guidance for various control options and recommendations for PPE based on a qualitative assessment of the chemical exposure. The published literature on CB revealed different models, each with varying levels of complexity and applicability. The utility of qualitative risk management strategies such as CB has been recognized by a number of international organizations. Widening interest in this strategy can be gauged by the growing literature describing elements of qualitative risk assessment and management strategies and in some cases, very well- developed models of practice. This report attempts to capture the state-of-the-science of CB as reflected in research and practice. From the published literature and information gleaned from proceedings of recent international workshops, symposia, and conferences on this subject, the following major themes related to CB have emerged: v • Factors influencing the evolution of qualitative risk characterization and management of occupational hazards • Strategies of practice • Applicability and limitations of practice • Needs for future research, evaluation, and validation These themes are based on interpretations of current studies and an understanding of the topic. By providing the appropriate background information and resources, this literature review can serve as a means to educate employers, workers, safety and health practitioners, and other audiences about the concepts of CB and to stimulate further dialogue about its potential usefulness in the United States. The scope of this document includes CB strategies, presented within the context of qualitative occupational risk management concepts. The risk management strategy associated with CB is characterized by selection and implementation of appropriate control solutions, often in the absence of OELs, to reduce work-related exposures that may lead to occupational disease, illness, and injury. The use of R-phrases or their equivalents in the Globally Harmonized System (GHS) for Classification and Labeling of chemicals in CB is a useful practice, but it is not intended to replace OELs, exposure assessment, or classic Industrial Hygiene protocol (i.e., hierarchy of controls) on which CB is based. This review indicates that CB is a potentially valuable tool for risk management of some chemical agents and other occupational hazards; however, continued research and validation efforts are needed. Investigation and application of CB principles to other hazardous agents also appear warranted. If CB is to be useful in the United States, it is recommended that the following actions occur: 1. Increase awareness and standardization of concepts associated with CB. 2. Ensure validation of qualitative risk assessment and management strategies, tools, and control-focused solutions. 3. Coordinate efforts for developing, implementing, evaluating, and disseminating qualitative risk assessment and risk management strategies to improve awareness and utility of task-specific, hazard-control guidance. 4. Foster national and international coordination on applications for control- focused solutions for high-risk tasks, industries, and small businesses. 5. Consider