Asbestos exposure in a Yale building. Analysis and resolution

Our plain-English summary of Asbestos exposure in a Yale building. Analysis and resolution, by R.N. Sawyer (Environmental Research, 1977).

The study

• Author: R.N. Sawyer
• Journal: Environmental Research
• Published: 1977;13(1):146-69
• Cited by: 38 articles, as counted by NIH iCite
• Read it: PubMed · Publisher
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 004370).

Abstract

The Yale University Art and Architecture building has 118,000 sq ft (10,000 m²) of floor space and houses the School of Art, the School of Architecture, and the schools’ library. Completed in 1963, the nine-level reinforced concrete structure is a major building on the campus and has been used by over 2000 persons each academic year. The ceiling material in the building, a spray-applied mixture of asbestos and fibrous glass, caused occupant exposure to asbestos fibers under all conditions of usual activity. The measured asbestos fiber concentrations in some situations exceeded Occupational Safety and Health Administration allowable limits for industrial exposure, and in all cases were above the ambient city levels. Many air samples indicated potentially carcinogenic asbestos exposures. To eliminate this health hazard, the asbestos was removed from the building. Building isolation, protective equipment, surfactant treated water, and decontamination procedures afforded contamination control for the workers and the surrounding community. Ninety-two tons of wet asbestos-contaminated material was removed during a 20-day operation. Over 500 air samples were obtained during surveillance, experimentation, and asbestos removal. This report presents data obtained from 200 samples examined to date and outlines procedures used in the operation.

PubMed has no abstract for this study. This is the authors' abstract, copied from the article.

In plain English

This 1977 report described air sampling in the Yale University Art and Architecture building, completed in 1963 and used by over 2000 people each academic year, and the removal of its sprayed ceiling material. That material was a mix of asbestos, fibrous glass and binder, about 15% chrysotile by weight. The study measured fibers in the air. It did not study disease in the building's users. Earlier tests in 1971, taken mostly in undisturbed conditions, found at most 0.5 fibers per cubic centimeter (f/cm3). In the author's later sampling, city air averaged 0.00 f/cm3 (12 samples), quiet rooms 0.02 (15 samples), usual activity by staff, students and faculty 0.2 (36 samples), dry dusting 4.0 (6 samples), and ceiling contact in the library stacks 15.5 (3 samples). In removal tests, plain water cut dry-removal fiber levels by about 75%, and water with an added wetting agent by 90%. Ninety-two tons of wet material were then removed. The author concluded that the building pointed to a widespread hazard. The author also noted that the consequences of low exposures are not defined.

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: Environmental exposure assessment and abatement report: air sampling of asbestos fibers in a single building during routine activities, reenacted tasks and experimental removal methods, followed by full removal of the ceiling material
• Who was studied: The Yale University Art and Architecture building in New Haven, Connecticut, completed in 1963 and used by over 2000 persons each academic year, including staff, students, faculty, custodians, tradesmen and removal workers; sampling took place in 1974 and 1975
• Exposure: Spray-applied ceiling material of asbestos, fibrous glass and cementitious binder covering 35,000 sq ft; chrysotile made up about 15% by weight. Fibers longer than 5 micrometers were counted by phase contrast microscopy.
• Main results:
  • The 1971 sampling, done mostly in undisturbed conditions, found a maximum of 0.5 f/cm3
  • Latex spray painting of the ceilings in 1972 was associated with a 67% reduction in mean fiber counts
  • Ambient city air within two blocks of the building averaged 0.00 f/cm3 (12 samples)
  • Building background in quiet conditions averaged 0.02 f/cm3 (15 samples)
  • Usual activity by staff, students and faculty averaged 0.2 f/cm3 (36 samples)
  • Custodial dry dusting averaged 4.0 f/cm3 (6 samples)
  • Ceiling contact in the library stacks averaged 15.5 f/cm3 (3 samples)
  • Compared with dry demolition, test ceiling removal cut fiber levels by about 75% with plain water and by 90% with surfactant-amended water
  • After test removal, airborne fibers took 30 hours to fall to background with dry removal, compared with 10 hours with amended water
  • Wet methods for custodial work reduced fiber levels, but not to zero detectable levels
  • Ninety-two tons of wet asbestos-contaminated material were removed
  • After the project, 24 samples examined so far averaged 0.0 f/cm3
  • In the workers' laundry operation, fiber levels reached a maximum of 1.2 f/cm3 and dropped to zero after one wash cycle
  • Electron microscopy found asbestos particles commonly present on settling-test samples that had zero counts by standard light microscopy
• The authors' conclusion: The author concluded that the building was not an isolated problem but pointed to a general, widespread hazard in other buildings with sprayed asbestos
• Limitations the authors state:
  • The OSHA standards and methods were used only as reference and comparison values, not as definitive markers of disease risk
  • Standard light microscopy gave zero counts on a filter carrying fibers shorter than 5 micrometers
  • Dry-removal exposures were higher than the reported counts, because fiber clumps were not counted
  • Much of the reenacted activity was not directly beneath the disturbed ceiling, implying higher peak exposures
  • The consequences of the low exposures most occupants experienced are not defined
  • Only 200 of over 500 samples had been examined when the report was written

Topics

Medical terms in this study, explained in our Lexicon: Asbestos Exposure, Carcinogenic.

Related studies

• Summary of the development of a signature for detection of residual dust from collapse of the World Trade Center buildings — H.A. Lowers, G.P. Meeker, et al. (2009)
• Airborne fiber control in buildings during asbestos material removal by amended water methodology — R.N. Sawyer, A.N. Rohl, et al. (1985)
• Community asbestos exposure in Globe, Arizona — R. Ing, H. Falk, et al. (1981)
• Worker exposure to asbestos during removal of sprayed material and renovation activity in buildings containing sprayed material — N.W. Paik, R.J. Walcott, et al. (1983)
• Asbestos release from whole-building demolition of buildings with asbestos-containing material — R.A. Perkins, J. Hargesheimer, et al. (2007)
• Physical characteristics and health effects of aerosols from collapsed buildings — S.H. Gavett (2006)

Browse more research in Environmental Research, or return to medical research.