History and evolution of warning labels for automotive friction products

Our plain-English summary of History and evolution of warning labels for automotive friction products, by L.M. Kopelovich, K.A. Thuett, P.S. Chapman, et al (Regulatory Toxicology and Pharmacology, 2014).

The study

• Authors: L.M. Kopelovich, K.A. Thuett, P.S. Chapman, D.J. Paustenbach
• Journal: Regulatory Toxicology and Pharmacology
• Published: 2014;68(3):402-11
• Type of article: Historical article
• Cited by: 3 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

There have been claims over the years that asbestos-containing product manufacturers did not sufficiently warn end users early enough regarding the potential health hazards associated with their products (1930s-1990s). To address this issue, we compared the content of the warnings associated with asbestos-containing friction products (brakes, clutches, and gaskets) manufactured by the US automotive industries to what was expected by regulatory agencies during the time period in which an understanding of asbestos health hazards was being developed. We ended our evaluation around 1990, since asbestos-containing manufacturer supplied automotive products were functionally removed from commerce by 1985 in the United States. We assessed the warnings issued in users' manuals, technical service bulletins, product packaging materials, and labels placed on products themselves. Based on our evaluation, regulatory agencies had no guidelines regarding specific warning language for finished friction products, particularly when a product contained encapsulated asbestos fibers (i.e., modified by a bonding agent). Even today, federal regulations do not require labeling on encapsulated products when, based on professional judgment or sampling, user exposure is not expected to exceed the OSHA PEL. We concluded that, despite limited regulatory guidance, the US automotive industry provided adequate warnings with regards to its friction products.

Copyright © 2014 Elsevier Inc. All rights reserved.

In plain English

This article was a historical review of warning labels, not a study of workers or disease. The authors, from the consulting firm Cardno ChemRisk, searched published literature, regulatory documents and corporate materials such as service manuals, technical service bulletins and package labels. They traced when and how warnings appeared for asbestos-containing automotive friction products. They noted that the chrysotile fibers in finished brakes and clutches were bound with resins. They reported no requirements for labeling asbestos-containing products before the 1970s and found no brake, clutch or gasket warnings from that time. The earliest warnings they identified were in a 1973 Chrysler service manual and on 1973 Bendix brake boxes. Later Ford, General Motors and Buick materials warned against compressed air and dry cleaning, and a 1993 Ford bulletin recommended non-asbestos parts. They reported that OSHA rules exempted bonded asbestos products from labeling under set exposure conditions. The authors concluded the industry's warnings were thorough and appropriate for their time. They stated the work had no automotive funding. They also disclosed that their firm has litigation clients and that at least one author has served as an expert witness for vehicle manufacturers.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: historical review and analysis of warning labels, regulations and literature
• Who was studied: Documents, not people: published literature, regulatory and government documents, and corporate materials (service manuals, user manuals, technical service bulletins, Material Safety Data Sheets, package labels) from US automotive manufacturers, covering roughly the 1930s to the 1990s, with reference to current (2013) rules
• Exposure: Asbestos-containing automotive friction products (brakes, clutches, gaskets); the authors describe the chrysotile fibers in finished brakes and clutches as encapsulated by phenolic resins or other bonding agents
• Main results:
  • Before the 1970s there were no requirements for labeling asbestos-containing products, and the authors found no brake, clutch or gasket warning labels from that period
  • The earliest friction-related warning the authors identified from an original equipment manufacturer was in a 1973 Chrysler Service Manual, which stated asbestos dust can be detrimental to health
  • A warning label appeared on Bendix brake boxes in 1973, cautioning against inhaling asbestos fibers
  • In 1975 a Ford Technical Service Bulletin warned against using compressed air during brake work; later manuals (1976 GM Delco Moraine, 1977 Chevrolet, 1985 Buick) gave cleaning instructions
  • Warning content varied across the industry in the 1970s because no standard warning language existed
  • The 1986 OSHA standard exempted products with bonded asbestos from labeling where exposure would stay below the action level; the authors state this exemption was intended for items such as brakes
  • A 1993 Ford Technical Service Bulletin warning recommended non-asbestos replacement parts whenever possible
  • As of 2013, the occupational standard for asbestos did not require warning labels on finished friction products
• The authors' conclusion: The authors concluded that the warning labels issued by automotive brake and clutch manufacturers were thorough and appropriate for their time, and that the US automotive industry was proactive in issuing warnings

Topics

The National Library of Medicine indexes this study under subjects our site covers: Auto mechanics and brake work.

Medical terms in this study, explained in our Lexicon: Friction Products, Gasket, Permissible Exposure Limit (PEL).

Related studies

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• History of knowledge and evolution of occupational health and regulatory aspects of asbestos exposure science: 1900-1975 — C.A. Barlow, J. Sahmel, et al. (2017)
• Asbestos in brakes: exposure and risk of disease — R.A. Lemen (2004)
• RE: Asbestos in brakes: exposure and risk of disease — M.J. Teta (2004)
• Environmental and occupational health hazards associated with the presence of asbestos in brake linings and pads (1900 to present): a "state-of-the-art" review — D.J. Paustenbach, B.L. Finley, et al. (2004)
• A study of airborne chrysotile concentrations associated with handling, unpacking, and repacking boxes of automobile clutch discs — G.C. Jiang, A.K. Madl, et al. (2008)

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