United States Office of Environmental Protection Toxic Substances Agency Washington, D.C. March 12, 1985 &EPA Asbestos-in-Buildings Technical Bulletin T . USE OF ASBESTOS-CONTAINING FRIABLE MATERIALS AND P VINYL-ASBESTOS FLOOR TILES IN PUBLIC AND COMMERCIAL BUILDINGS INTRODUCTION A national survey was recently completed by EPA to determine the incidence of asbestos-containing friable materials (ACFM) in public and commercial buildings other than schools. (Friable materials are materials that can be crumbled, pulverized, or reduced to powder in the hand.) The survey was an effort to deal with the broad problem of public exposure to ACFM. Previous estimates of the number of buildings that contain asbestos ranged from 5 to 45 percent with an unknown degree of accuracy because they were based on anecdotal information or expert opinion. No valid national estimates existed and this wide range did not satisfy the Agency's information needs. Thus, a national survey was undertaken to produce more preci se and statistically valid estimates with a known degree of accuracy that can be used to support the Office of Toxic Substances' technical assistance and regulatory programs. The study also gathered data on the incidence of vinyl-asbestos floor tiles in the buildings surveyed as no data on this incidence were previously available. HOW THE SURVEY WAS CONDUCTED Public and commercial structures include government build- ings, apartments, office buildings, hospitals, restaurants, and all types of wholesale and retai1 establishments. In general , they are buildings which are either accessible to the public, or, as a group, are occupied by a large fraction of the population. Altogether, public and commercial buildings in the U.S. number more than four million. For purposes of the survey, three categories of structures were sampled to represent all of these buildings: federally owned or leased (excluding the military), private residential (apartment buildings with 10 or more units), and private nonresidential (retail and some wholesale establishments and office buildings). 11 was not practical to include all categories due to the lack of adequate building lists for sampling for some, or the infrequent use or low occupancy of others. The buildings represented in the survey number around 3.6 million. 231 Buildings Were Inspected The statistical design of the survey ensured that a repre- sentative sample of buildings was selected and that survey results could be reliably projected to the entire population of buildings. A total of 231 buildings were inspected. Of ------- 2 these, roughly one-fourth were federal buildings, one-fourth were private residential structures, and one-half were private nonresidential buildings. Ten different sites (cities or groups of counties) across the country were included in the sample to ensure geographic representativeness. Buildings of various sizes, ages, and construction materials were also included in the sample design. All Bulk Materials Were Sampled The inspection process was designed to ensure uniformity of inspection for all buiIdings in the sample, and thoroughness within each building. Standard EPA protocols were employed in the sampling of bulk materials to ensure the representa- tiveness of samples of sprayed- or troweled-on materials and, where possible, ceiling tile. Convenience samples were taken of pipe and boiler wrap, some ceiling tile, and floor tiles to avoid damaging or affecting the cosmetic appearance of the areas. Laboratory analyses of the bulk samples for asbestos followed the EPA protocol for polarized light microscopy. The laboratory analysis for asbestos in floor tiles required some developmental work to determine an effective sample preparation method. Each building in the sample was inspected for the presence of materials that may contain asbestos: friable sprayed- or troweled-on materials, ceiling tile, pipe and boiler insulation, and floor tile. Over 1500 samples of suspect materials were collected and analyzed for asbestos. These included approximately 500 floor tile samples. Rigorous A rigorous quality assurance program was employed throughout Quality the study. At all stages of the analysis, work was reviewed Assurance for consistency with established procedures for data collec- Program tion and transmittal. In addition, laboratory analyses of bulk materials were checked by randomly collecting side-by-side samples and analyzing them in different laboratories. Routine quality control procedures were also utilized in each laboratory. SUMMARY The survey was designed to provide information on the OF RESULTS number of buildings with different types of ACFM, the extent of ACFM usage, and the degree to which usage differs among different types of buildings. ------- 3 20% of All Buildings Have ACFM About 20 Ipercent (733,000) of all public and commercial buildings are estimated to have some type of ACFM. Roughly five percent have ACFM sprayed- or troweled-on beams, ceilings or walls, and approximately 16 percent have asbestos-containing pipe and boiler insulation. Very few buildings (less than one-half percent) are estimated to have asbestos-containing ceiling tile. An estimated 1,526,000 buildings, or 42 percent of buildings surveyed have asbestos- containing floor tiles. The incidence of ACFM varies appreciably among the three categories of buildings. Federal government (39 percent) and private residential (59 percent) structures are estimated to have substantially higher incidence, and private nonresidential structures (16 percent) are estimated to have substantially lower incidence. Similar patterns were found for asbestos floor tiles. 1.2 Billion Square Feet of Sprayed- or Troweled-on ACFM Based on the survey results, about 1.2 billion square feet of beams, ceiling, and walls are estimated to be covered by sprayed- or troweled-on ACFM. Asbestos-containing floor tiles cover about 2.7 billion square feet. A similar measure of the extent of use of pipe and boiler wrap is not available. Recall, however, that the incidence of pipe and boiler wrap is substantially higher than that of sprayed or troweled-on ACFM. Sixteen percent or 550,000 buildings are estimated to have asbestos-containing pipe and boiler insulation. However, the building inspections also revealed that most pipe and boiler insulation is found in restricted-access areas, thus reducing potential exposure for building occupants other than custodial and maintenance personnel. Percent of Asbestos in ACFM Varied Results of the laboratory analyses revealed that the asbestos content of pipe and boiler wrap was much higher than sprayed- or troweled-on ACFM: roughly 70 percent compared to 14 percent. The small amount of asbestos-containing ceiling tile found in the sample of buildings has a very low asbestos content: about three percent. Asbestos content of floor tiles is 12 percent. The only significant difference in the asbestos content of ACFM among the three building types was a higher asbestos content in sprayed- or troweled-on materials found in federal buildings (29 percent compared with the average of 14 percent for all buildings). It is important to keep in mind that the asbestos content of building materials may not be a good single indicator of ------- 3 20% of All Buildings Have ACFM About 20 Ipercent (733,000) of all public and commercial buildings are estimated to have some type of ACFM. Roughly five percent have ACFM sprayed- or troweled-on beams, ceilings or walls, and approximately 16 percent have asbestos-containing pipe and boiler insulation. Very few buildings (less than one-half percent) are estimated to have asbestos-containing ceiling tile. An estimated 1,526,000 buildings, or 42 percent of buildings surveyed have asbestos- containing floor tiles. The incidence of ACFM varies appreciably among the three categories of buildings. Federal government (39 percent) and private residential (59 percent) structures are estimated to have substantially higher incidence, and private nonresidential structures (16 percent) are estimated to have substantially lower incidence. Similar patterns were found for asbestos floor tiles. 1.2 Billion Square Feet of Sprayed- or Troweled-on ACFM Based on the survey results, about 1.2 billion square feet of beams, ceiling, and walls are estimated to be covered by sprayed- or troweled-on ACFM. Asbestos-containing floor tiles cover about 2.7 billion square feet. A similar measure of the extent of use of pipe and boiler wrap is not available. Recall, however, that the incidence of pipe and boiler wrap is substantially higher than that of sprayed or troweled-on ACFM. Sixteen percent or 550,000 buildings are estimated to have asbestos-containing pipe and boiler insulation. However, the building inspections also revealed that most pipe and boiler insulation is found in restricted-access areas, thus reducing potential exposure for building occupants other than custodial and maintenance personnel. Percent of Asbestos in ACFM Varied Results of the laboratory analyses revealed that the asbestos content of pipe and boiler wrap was much higher than sprayed- or troweled-on ACFM: roughly 70 percent compared to 14 percent. The small amount of asbestos-containing ceiling tile found in the sample of buildings has a very low asbestos content: about three percent. Asbestos content of floor tiles is 12 percent. The only significant difference in the asbestos content of ACFM among the three building types was a higher asbestos content in sprayed- or troweled-on materials found in federal buildings (29 percent compared with the average of 14 percent for all buildings). It is important to keep in mind that the asbestos content of building materials may not be a good single indicator of ------- |