Contents

Foreword

The Occupational Safety and Health Act of 1970 (Public Law 91–596) assures, insofar as possible, safe and healthful working conditions for every working man and woman in the Nation. The act charges the National Institute for Occupational Safety and Health (NIOSH) with recommending occupational safety and health standards and describing exposure concentrations that are safe for various periods of employment—including but not limited to the concentrations at which no worker will suffer diminished health, functional capacity, or life expectancy as a result of his or her work experience.

This document represents the collaborative efforts of industry, labor, and government to protect the health of workers exposed to asphalt fumes during the manufacture of asphalt roofing products. Current engineering controls and work practices are presented for reducing worker exposures to asphalt fumes during the manufacturing process. These prevention methods are the cornerstone of public and occupational health.

This document is the result of a public meeting convened on July 22 and 23, 1996, in Cincinnati, Ohio. Participants discussed engineering controls and work practices for controlling exposures to asphalt fumes in the roofing industry. Although the health risks from asphalt exposure are not yet fully defined, all partners agreed that prudent action was needed to reduce worker exposures. They decided to produce a joint document that would describe engineering controls and work practices to reduce worker exposure to asphalt fumes during the manufacture of asphalt roofing products. The willingness of all partners to work together in this effort should serve as a model for others who are developing occupational safety and health recommendations. This document was truly a joint effort. I would like to thank the National Roofing Contractors Association (NRCA), the Asphalt Roofing Manufacturers’ Association (ARMA), the Asphalt Institute (AI), and the United Union of Roofers, Waterproofers, and Allied Workers for their cooperation and hard work.

Kathleen M. Rest, Ph.D., M.P.A.
Acting Director, National Institute for
Occupational Safety and Health
Centers for Disease Control and Prevention

Abstract

This document represents a collaborative effort of the National Institute for Occupational Safety and Health (NIOSH), the National Roofing Contractors Association (NRCA), the Asphalt Roofing Manufacturers’ Association (ARMA), the Asphalt Institute (AI), and the United Union of Roofers, Waterproofers, and Allied Workers to reduce worker exposures to asphalt fumes during the manufacture of asphalt roofing products. The document describes the manufacturing process, identifies steps in the process with the potential for asphalt fume exposure, and identifies current engineering control methods and work practices used to reduce exposures. In addition, the document lists relevant research needed for further reducing asphalt fume exposures during the manufacture of asphalt roofing products.

Introduction

The primary purpose of this document is to increase awareness among plant managers, safety and health professionals, and engineers of the potential for occupational exposure to asphalt and asphalt fumes during the manufacture of asphalt roofing products. The document represents a collaborative effort of industry, labor, and government. During public meetings held in Cincinnati, Ohio (July 22–23, 1996), several groups agreed to develop a series of documents that (1) describe the extent of asphalt exposure during the production of asphalt roofing products and during asphalt roofing operations, and (2) provide information about measures to reduce exposures. These groups included the National Roofing Contractors Association (NRCA); the Asphalt Roofing Manufacturers’ Association (ARMA); the Asphalt Institute (AI); the United Union of Roofers, Waterproofers, and Allied Workers; and the National Institute for Occupational Safety and Health (NIOSH). This document identifies work practices and other control measures that, when available, may be effective in reducing worker exposures to asphalt fumes during the manufacture of asphalt roofing products.

In 2000, NIOSH conducted a review of the health effects data on asphalt that had become available since the publication of the 1977 criteria document on asphalt [NIOSH 2000]. This review addresses acute and chronic effects and is available at the NIOSH Web site (www.cdc.gov/niosh) for readers interested in additional information.

NIOSH, labor, and industry are working together to better characterize and quantitate the health risks from asphalt exposure. Representatives of industry, labor, government, and academia met in Cincinnati, Ohio, on September 11 and 12, 2000, and identified research to assess completely the health risks associated with exposure to asphalt. Through these and other efforts of this partnership, effective workplace measures can be implemented to reduce worker exposure to asphalt fumes.

Background

Composition and Uses of Asphalt

Asphalt (CAS* No. 8052–42–4) is a dark brown to black, cementitious, thermoplastic material found in a natural state or (more commonly) manufactured in petroleum refineries by atmospheric or vacuum distillation; it may also be left as residue after evaporating or otherwise processing crude oil or petroleum. Asphalt is solid or highly viscous at ambient temperatures. This material is an extremely complex mixture containing a large number of highmolecular- weight organic compounds [King et al. 1984]. Asphalt is now the dominant material in roofing in the United States. However, coal tar is still used in some roofing work, usually to conform to government building specifications that require the use of coal tar [Freese and Nichols, Inc. 1994].

Most of the asphalt used in the United States is used in paving (87%) and roofing (11%) operations. Only about 1% is used for waterproofing, damp proofing, insulation, paints, and other activities [AI 1990a]. Asphalt roofing products and systems include shingles and roll roofing, ply felt, built-up roofing (BUR) systems, saturated felt used as underlay for shingles, and modified bitumen systems. These products and systems are described in Section 2.4.

Research Needs

The following research is suggested to reduce the risk of adverse health effects from occupational exposure to asphalt fumes during the manufacture of asphalt roofing products:

• Characterization of worker exposure to asphalt fumes in this segment of the industry (of particular interest are exposures during high-temperature operations)
• Identification of short-term peak exposures as well as work shift TWA exposures
• Determination of the effectiveness of current engineering controls in reducing worker exposure to asphalt fume

Acknowledgements

This document was prepared by the staff of the National Institute for Occupational Safety and Health (NIOSH) in collaboration with representatives of the Asphalt Institute (AI), the Asphalt Roofing Manufacturers’ Association (ARMA), the National Roofing Contractors Association (NRCA), and the United Union of Roofers, Waterproofers, and Allied Workers. Paul A. Schulte, Director, Education and Information Division (EID), had overall responsibility for the document. Joann Wess (NIOSH) was the project director.

The following contributors are gratefully acknowledged: Heinz Ahlers, J.D. (NIOSH); Tom Calzavara (ARMA); William Candy (ARMA); Bill Fayerweather, Ph.D. (ARMA); Jerome Flesch (NIOSH); Bill Good (NRCA); Jude LaPerouse (NRCA); David Marlow (NIOSH); Bernie McCarthy (AI); Leroy Mickelsen (NIOSH); Dennis Mueller (ARMA); Larry Olsen, Ph.D. (NIOSH); Klaus Rosinski, Ph.D. (ARMA); Arthur Sampson (ARMA); Tom Shanahan (NRCA); Richard Snyder (ARMA); Russ Snyder (ARMA); Marie Haring Sweeney, Ph.D. (NIOSH); Alex Teass, Ph.D. (NIOSH); and Ralph Zumwalde (NIOSH).

Vanessa Becks, Richard Carlson, Judy Curless, Susan Feldmann, Anne Hamilton, Susan Kaelin, and Jane Weber (NIOSH) provided editorial support and contributed to the design, graphics, and layout of this document.

Disclaimer

Ordering Information

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DHHS (NIOSH) Publication No. 2001-127

August 2001