Technological feasibility of the 2 fibers/cc asbestos standard in asbestos textile facilities

Our plain-English summary of Technological feasibility of the 2 fibers/cc asbestos standard in asbestos textile facilities, by R.A. Curtis, P.H. Bierbaum (American Industrial Hygiene Association Journal, 1975).

The study

• Authors: R.A. Curtis, P.H. Bierbaum
• Journal: American Industrial Hygiene Association Journal
• Published: 1975;36(2):115-25
• Cited by: 3 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

The technical feasibility of developing dust control practice which would bring the asbestos industry into compliance with the OSHA I fibers/cc standard, scheduled to become effective July 1, 1976, has been questioned since its promulgation. This paper presents the results of industrial hygiene surveys, including the results of 243 asbestos air samples, conducted at two asbestos textile production facilities which have achieved the 2 fibers/cc standard. Both facilities use nonconventional production techniques. Conclusions drawn from the investigations express the need for: (1) a study of new products; (2) a tool to motivate consumers to switch to the new products when appropriate; and (3) legislation which will protect all domestic producers of asbestos textiles from certain producers who do not have to absorb the added expense of meeting the OSHA standard.

In plain English

The authors examined whether asbestos textile plants could keep workers' airborne asbestos exposures below the 2 fibers/cc standard set by OSHA. After visiting five plants that manufacturers offered as models, they surveyed two limited production plants and collected 243 asbestos air samples. Plant A used a modified carding process. Plant B formed yarn from wet chemical dispersions of chrysotile. Plant A had 148 personal samples. Its dustiest area, carding, averaged 0.8 fibers/cc, and only one sample there was above 2 fibers/cc. Plant B had 95 personal samples. Its yarn-forming area averaged less than 0.1 fibers/cc. In its combined spinning/twisting and winding area, levels were higher on the first sampling day, which the authors attributed to processing yarn that had been allowed to dry. The authors concluded that both methods could keep exposures below 2 fibers/cc. They cautioned that this did not show the whole asbestos textile industry could meet the standard, because both plants were limited production facilities and their methods limited the kinds of products they could make.

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: Industrial hygiene surveys with personal air sampling at two asbestos textile plants. The aim was to find plants whose dust control methods met the OSHA 2 fibers/cc standard. No health outcomes were studied.
• Who was studied: Two asbestos textile plants (Plant A and Plant B), both limited production facilities. They were chosen from five plants visited after six manufacturers were contacted. In total, 243 asbestos air samples were taken from workers' breathing zones: 148 at Plant A and 95 at Plant B. The Plant A survey is dated October 1973 in the article's table. No date is given for Plant B.
• Exposure: Airborne asbestos fibers longer than 5 micrometers, counted by phase contrast microscopy. Exposures were measured in carding, twisting, winding, weaving, braiding and related jobs. Plant B's liquid dispersion process is based on chrysotile dispersions. The article does not name the fiber type used at Plant A.
• Main results:
  • Plant A, carding area: mean 0.8 fibers/cc across 44 samples. One sample was above 2 fibers/cc, 10 were between 1 and 2 fibers/cc, and 33 were below 1 fiber/cc.
  • Plant A, other operations: mean concentrations were 0.5 fibers/cc in twisting, 0.3 fibers/cc in winding, 0.6 fibers/cc in weaving and 0.2 fibers/cc in braiding.
  • Plant A: the authors reported that the process modifications had lowered exposures to less than one-tenth of the levels found two years earlier.
  • Plant B: 95 personal samples were taken. Typical concentrations in the yarn-forming area averaged less than 0.1 fibers/cc.
  • Plant B, spinning/twisting and winding area: the average was 1.12 fibers/cc on the first sampling day, 0.41 fibers/cc on the second and 0.25 fibers/cc on the third. The authors attributed the higher first-day level to processing yarn packages that had been allowed to dry.
  • Plant B: mean concentrations in weaving (0.24 fibers/cc) and braiding (0.06 fibers/cc) were described as surprisingly low, because visible dust was seen during sampling. The mean in the cloth cleaning area was 0.03 fibers/cc.
• The authors' conclusion: The authors concluded that the modified carding and liquid dispersion methods can produce asbestos textile products while keeping airborne exposures below 2 fibers/cc. They added that the success of these methods will depend on whether the products are acceptable and marketable. They also said it would be improper to conclude from these results alone that the asbestos textile industry as a whole can technically meet the standard.
• Limitations the authors state:
  • Both plants were limited production facilities. Exposures might increase at full production, although the authors thought it doubtful that levels would rise above the standard.
  • The production techniques limited the kinds of products made. Lap and roving were not produced. Asbestos content was capped at 95% at Plant A and was at least 99% at Plant B. Neither method can make dry processed products.
  • The very low levels at Plant B may be stretching the limits of the NIOSH fiber counting method.
  • Details of Plant B's process were proprietary and were left out of the paper.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Asbestos textiles.

Medical terms in this study, explained in our Lexicon: Dust Control, OSHA, Industrial Hygiene, Asbestos Textiles.

Related studies

• Health progress in an asbestos textile works — J. Mitchell (1961)
• Implementation of the federal asbestos standard in Connecticut — J.B. Schoenberg, C.A. Mitchell (1974)
• Dust control in a conventional asbestos textile factory — H.C. Lewinsohn, C.A. Kennedy, et al. (1979)
• Estimates of historical exposures by phase contrast and transmission electron microscopy in North Carolina USA asbestos textile plants — J.M. Dement, D. Myers, et al. (2009)
• Estimates of historical exposures by phase contrast and transmission electron microscopy for pooled exposure--response analyses of North Carolina and South Carolina, USA asbestos textile cohorts — J.M. Dement, D. Loomis, et al. (2011)
• Hygiene standards for asbestos — S.A. Roach (1970)

Browse more research in American Industrial Hygiene Association Journal, or return to medical research.