Only rarely does a clear opportunity present itself to demonstrate how the sometimes esoteric research we do in academia can affect the safety and health of workers. Such an opportunity was afforded by the publication of the final rule on respiratory protection by the Occupational Safety and Health Administration (OSHA) on January 8 of this year.
Respirators are the last line of defense against hazardous airborne exposures in the workplace. Thus, they play a critical role when other controls do not adequately protect a worker. It is estimated that OSHA's new rule will impact five million respirator wearers in some 1.3 million workplaces in the United States.
Featured conspicuously in several of the key technical sections of the standard is the work of COEH faculty member Mark Nicas, alumna Kit Galvin, and a supporting cast, including myself. Here I exert the director's prerogative to report not news, but a short history of the background of our contribution to the OSHA rule, because it illustrates so well the interaction of professional experience, student research, and faculty theorizing that can provide the scientific basis for decisions about state and federal health and safety standards.
In the early 1980s, Steve Rappaport, then a Berkeley faculty member, initiated a line of research focusing on the use of statistical methods to characterize occupational exposures to airborne chemicals. Biostatistics Professor Steve Selvin and I joined Rappaport's efforts and, when Rappaport took sabbatical leave in the mid-'80s, we ended up responsible for a study of benzene exposures in the petroleum refining industry. Out of this work, with then-doctoral students Marcie Francis and Jane Schulman, came the application of a statistical model which acknowledged that workplace exposures often needed to be considered in terms of the individual as well as the job.
Roughly coincident with the benzene study, Nicas was working for the Cal/OSHA Research and Standards Unit on issues related to respirators. In this job, he came to have concerns about the amount of protection various types of respirators provided to workers and how variable this protection might be from day-to-day and person-to-person. In 1986 he entered our doctoral program and learned how, in the benzene study, we were dealing with issues of day-to-day and person-to person variability in exposure. He applied these ideas to the respirator issue, and, in 1987, published the first of several papers which now form the theoretical underpinning of a central part of the 1998 OSHA rule.
About the same time, Nicas convinced us that there was a paucity of data about the variability of respiratory protection in the workplace, particularly for gases and vapors. Kit Galvin, then a master's student in Berkeley's industrial hygiene program, signed on to gather this data for her thesis project. The paper that grew out of her work is the only field study of respiratory protection for gases and vapors listed in the OSHA rule under "Studies Reflecting Good Program Elements"that is, studies that show the degree of protection to be expected in workplaces with proper respirator programs. Parenthetically, a key aspect of Galvin's work relied on modeling studies of styrene toxicology and metabolism being carried out by Elin Kure, another COEH doctoral student at that time.
So, 11 years after Nicas' first theoretical publication on variability in respiratory protection, the line of work he initiated and pursued has culminated not only in new knowledge but also in an important policy change, potentially protecting millions of American workers. For our present students, there is a subsidiary message that all the theory they encounter is not without practical importance.
Finally, note that the dissertation research of J.D. Wu, described in this issue, is much in the spirit of Nicas' early work, in that it explores how to describe the characteristics of multivariate exposure data on the one hand and how to integrate quantitative and qualitative features on the other. Hopefully, in 10 or 15 years, another COEH director will have the pleasure of discussing its practical impact on worker protection.
Robert C. Spear Director