The American Iron and Steel Institute (AISI) gathered data between 1989 and 1997 to build an \"objective database\" to further understand the occupational exposures generated by the few asbestos-containing materials remaining at various steelmaking companies at this time. This paper analyzed the 520 samples from this campaign which occurred at five different steel manufacturers: Georgetown Steel Company, Inland Steel Company, Ling-Temco-Vought (LTV) Corporation, United States Steel Corporation, and Weirton Steel Corporation. This database is believed to have never previously been systematically organized. Samples were grouped based on sampling times to determine whether they should most appropriately be compared to the OSHA short-term excursion limit (EL) or the 8-hr time-weighted average (TWA) permissible exposure limit (PEL). Sampling times of 30 min or less were considered short-term samples, and samples of 180 min or greater were considered representative workday samples. Samples that did not fit into either category, with sampling times between 31 and 179 min, were considered task samples. Overall, the data indicated that the airborne concentrations were quite low in 1989 and they continued to be low through the study period which ended in 1997. Only seven out of 286 (approximately 2.5%) short-term or representative workday samples were in exceedance of the current OSHA OELs that were implemented in 1994 (short-term samples being compared to the 1 f/cc EL and representative workday samples being compared to the 0.1 f/cc 8-hr TWA PEL). Consistent with prior data, analysis of this dataset supports the view that materials containing asbestos were not used in many applications in the steel industry, and measured airborne concentrations of asbestos were almost always below the occupational exposure limits (OELs) in the post-OSHA era (1972-2000).

BACKGROUND: Historically, the use of asbestos in steelmaking has been limited to a few applications. Due to its physical and chemical properties, asbestos was not necessary or suitable for most purposes in a steel mill. The few applications where asbestos were used (i.e., certain gaskets, brakes, protective cloth, refractory materials, insulation materials, and hot top products) were replaced by alternative materials as they became available.
OBJECTIVE: We discuss historical uses of asbestos in steel manufacturing and the associated airborne asbestos concentrations collected at sixteen U. S. Steel facilities between 1972 and 2006.
METHODS: A total of 495 personal airborne asbestos samples from the U. S. Steel industrial hygiene records were analyzed across four time periods corresponding to changes in the OSHA permissible exposure limit (PEL) for asbestos. 68% of the samples (n = 337) were considered representative of an employee\'s workday. The remaining samples (n = 158) represented task samples. Samples were grouped by facility, department, and job category within the four time periods.
RESULTS: The average fiber concentrations measured for each facility and department over time were below the contemporaneous OSHA PEL. The mean representative workday asbestos air concentration from 1972 and 1975 was 1.09 f/cc. The mean representative workday concentration decreased to 0.13 f/cc between 1976 and 1985, then decreased again to 0.02 f/cc between 1986 and 1993 and 0.03 f/cc between 1994 and 2006. For task samples, the mean air concentration from 1972 to 1975 was 3.29 f/cc. The mean task sample concentration decreased to 0.48 f/cc between 1976 and 1985, then decreased again to 0.01 f/cc between 1986 and 1993 and 0.03 f/cc between 1994 and 2006. Only eleven out of the 495 samples (2.2%), for both task and representative workday samples, were in exceedance of the contemporaneous PEL(as an 8-hour TWA), ten of which occurred prior to 1978. Eight of these eleven PEL exceeding samples were task samples. Of the remaining three representative workday samples, two had unknown sampling times.
CONCLUSIONS: This paper presents an analysis of all the available personal sampling data for airborne asbestos across 16 facilities of the U. S. Steel Corporation between 1972 and 2006. This dataset has previously never been publicly shared or analyzed. It represents one of the more complete industrial hygiene datasets from a corporation to be presented in a scientific journal and, due to the similarities in the processes at each mill, it should reflect analogous exposures throughout the steelmaking industry in the United States. One of the benefits of presenting these data is that it also provides insight into where asbestos-containing materials (ACMs) were used in the steel making process. This is just one example of a large firm that released information that had previously remained in file cabinets for decades. We believe that another benefit of publishing this paper is that it may encourage the largest firms in industry to assemble and analyze their industrial hygiene data to benefit the occupational hygiene, medical, and epidemiology communities. This can support future epidemiology studies and improve the design of future industrial hygiene programs.

The objective is to present historical asbestos airborne concentrations associated with activities involving presumably asbestos-containing materials in steel mills. A total of 138 historical industrial hygiene air samples collected in three US steel mills from 1972 to 1982 were analyzed. The majority of samples were collected during relining of open hearth furnaces, stoves, and blast furnaces by steel mill bricklayers and bricklayer helpers. Over 75% of the samples (n = 106) were collected for 50 min or less, four samples were collected for 227 to 306 min, and sample durations were not reported for the remaining 28 samples. Average airborne fiber concentrations measured during relining activities of open hearth furnaces, stoves, and blast furnaces were 0.21 f/cc, 0.72 f/cc and 0.13 f/cc phase-contrast microscopy (PCM), respectively. Measured airborne fiber concentrations of four time-weighted average (TWA) samples (>227 min) averaged 0.045 f/cc. Estimated 8-h TWAs concentrations averaged 0.34 f/cc for bricklayers and 0.2 f/cc bricklayer helpers. While 8-h TWA concentration estimates for monitored tasks/jobs may often have exceeded current Occupational Safety and Health Administration (OSHA) Permissible Exposure Limits (PELs), they did not exceed relevant contemporaneous occupational exposure standards. This analysis provides a better understanding of historical airborne asbestos exposures that bricklayers and other tradesmen experienced during furnace and stove work in the US steel mills.