Purple Book (Guide Controlling ACM in Buildings) PDF

SUMMARY OF GUIDANCE INTRODUCTION Airborne asbestos contamination in buildings is a significant environmental problem. Various diseases have been linked with industrial exposure to airborne asbestos, and the extensive use of asbestos products in buildings has raised concerns about exposure to asbest...

SUMMARY OF GUIDANCE INTRODUCTION Airborne asbestos contamination in buildings is a significant environmental problem. Various diseases have been linked with industrial exposure to airborne asbestos, and the extensive use of asbestos products in buildings has raised concerns about exposure to asbestos in nonindustrial settings. Surveys conducted by the Environmental Protection Agency (EPA) estimate that asbestos containing materials can be found in approximately 31,000 schools and 733,000 other public and commercial buildings in this country. The presence of asbestos in a building does not mean that the health of building occupants is necessarily endangered. As long as asbestos-containing material (ACM) remains in good condition and is not disturbed, exposure is unlikely. When building maintenance, repair, renovation or other activities disturb ACM, or if it is damaged, asbestos fibers are released creating a potential hazard to building occupants. Although not required to do so by federal law, the prudent building owner will take steps to limit building occupants’ exposure to airborne asbestos. In 1983 EPA prepared and distributed “Guidance for Controlling Friable Asbestos-Containing Materials in Buildings” (USEPA 1983a). Since this guidance was published, EPA has gathered additional information and has gained valuable experience through its continuing Asbestos-inBuildings Program. The guidance document has been substantially revised to incorporate this new information and to reflect the comments and suggestions of building owners and other readers. EPA offers building owners guidance to understand the technical issues, determine if asbestos is present in a building, plan a control program, and choose the course of further action if necessary. This summary is divided into two parts. The first is an introduction to the problem of asbestos in buildings and summarizes the material that is presented in Chapter 1. The second part of the summary provides a concise outline of the remainder of the report. It lists the major steps needed to determine whether asbestos is present in a building (Chapter 2), establish a special operations and maintenance (O&M) program (Chapter 3), assess the need for further action (Chapters 4 and 5), and carry out an abatement project (Chapter 6). It is intended as a checklist for the building owner. ACM IN BUILDINGS ACM in buildings is found in three forms: (1) sprayed or troweled on ceilings and walls (surfacing material); (2) in insulation around hot or cold pipes, ducts, boilers, and tanks (pipe and boiler insulation); and (3) in a variety of other products such as ceiling and floor tiles and wall boards (miscellaneous materials). In general, ACM in the first two categories is of greatest concern, especially if it is friable. (Friable material can be crumbled, pulverized, or reduced to powder by hand pressure.) Testing for ACM is required in primary and secondary schools only. (Regulations are specified in ‘ (The Friable Asbestos-Containing Materials in Schools; Identification and Notification Rule.”) At present, no parallel rule applies to other public or commercial buildings. Further, no Federal regulations require abatement actions (repair or removal, enclosure, encapsulation). The OSHA (Occupational Safety and Health Administration) regulations specifying work practices and the EPA rules governing the handling and disposal of asbestos apply to abatement actions. State regulations on these issues vary and may be more stringent than federal requirements. ASBESTOS CONTROL ACTIVITIES The following pages outline the steps that a building owner should take to control asbestos. Each step is described in more detail in the body of the report. S-1 Survey to See if Asbestos is Present ● Appoint an asbestos program manager and assemble a survey team. ● Check building records for evidence of asbestos- containing surfacing materials, pipe and boiler insulation, or miscellaneous ACM. ● Locate and document all ACM identified in building records. ● Inspect the building for friable materials on walls or ceilings. Inspection means touching walls and ceilings. ● Inspect the building for insulation on pipes and boilers. Inspection means looking at pipes and boilers. ● Be persistent. Friable materials may be hidden behind dropped ceilings or partitions, ● Collect samples of friable ceiling and wall materials following EPA procedures. ● Collect samples of pipe and boiler wrap if the insulation is exposed. Otherwise, assume the insulation contains asbestos. ● Send samples to a qualified laboratory for analysis by polarized light microscopy (PLM). If the samples show more than one percent asbestos, the building contains ACM, ● Document all findings. Establish a Special Operations and Maintenance (O&M) Program ● Obtain cooperation of building maintenance and custodial managers. ● Educate building occupants and employees about ACM. ● Tram custodial and maintenance workers in special cleaning techniques and maintenance precautions, ● Clean the building thoroughly using wet cleaning and HEPA-vacuum techniques. ● Repeat the cleaning monthly (near surfacing materials) or semi-annually (near wrapped insulation). ● Take special precautions before starting maintenance and construction work. ● Inspect ACM at least twice a year for evidence of damage or deterioration. ● Continue the O&M program until all ACM is removed. Assess the ACM to Determine the Need for Further Action ● Assess the likelihood of fiber release from the ACM by evaluating its current condition and the potential for future disturbance, damage or erosion. ● Determine: S-2 — The need for further action. — When it should be done. — What abatement method should be used. Conduct Abatement Actions if Needed ● Hire an abatement contractor or, if in-house capabilities are available, use building staff. ● To select a contractor: — Write precise contract specifications. — Check references. — Conduct interviews. — Review insurance coverage. — Select the “best” contractor, not necessarily the lowest bidder. ● To Manage the work: — Inspect the work site at least four times a day to insure compliance with all prescribed work practices and worker protection measures. These include: * Construction of a containment barrier around the entire work area, or the use of containment bags for wrapped insulation. * Use of coveralls and respirators by the workers. * Provision of worker change and decontamination facilities. — Stop abatement work immediately if any condition of the worksite appears to be hazardous. — Release the contractor only after: * The work site has been thoroughly cleaned at least twice. * The work site passes a visual test for abatement completion and cleanliness. * The work site passes a test for airborne asbestos. S-3 CHAPTER 1. BACKGROUND ON EXPOSURE TO ASBESTOS INSIDE BUILDINGS Construction materials containing asbestos have been used extensively in schools and other buildings. The concern about exposure to asbestos in these buildings is based on evidence linking various respiratory diseases with occupational exposure in the shipbuilding, mining, milling, and fabricating industries. The presence of asbestos in a building does not mean that the health of building occupants is endangered. If asbestos-containing material (ACM) remains in good condition and is unlikely to be disturbed, exposure will be negligible. However, when ACM is damaged or disturbed — for example, by maintenance or repairs conducted without proper controls — asbestos fibers are released. These fibers can create a potential hazard for building occupants. This chapter describes ACM found in buildings and the potential health risks to occupants of buildings where ACM is present. Also, federal regulations addressing asbestos in buildings are briefly summarized. SUMMARY ACM in Buildings: Three forms of asbestos are typically found in buildings: (1) sprayed-or troweledon surfacing materials; (2) insulation on pipes, boilers, and ducts; and (3) miscellaneous forms, such as wallboard, ceiling tiles, and floor tiles. EPA surveys estimate that 31,000 schools and 733,000 public and commercial buildings contain friable (easily crumbled) ACM. Friable ACM and ACM disturbed during maintenance, repair or renovation are of greatest concern from an exposure perspective. Levels of Airborne Asbestos in Buildings and Other Settings: Prevalent levels of airborne asbestos inside buildings with ACM may be 10 to 100 times higher than outdoor levels. However, these indoor levels are typically 10,000 to 100,000 times lower than levels in asbestos industry workplaces where asbestos-related diseases have been well-documented. Asbestos-Related Disease: Most people with asbestos-related diseases (asbestosis, lung cancer, and mesothelioma) were exposed to high levels of asbestos while working in asbestos industries prior to 1972. Extrapolation of the relationship between exposure level and disease indicates that only a small proportion of people exposed to low levels of asbestos will develop asbestos-related diseases. Smokers, children, and young adults are at somewhat greater risk. Federal Regulations Regarding Asbestos in Buildings: Current regulations (1) restrict the use of most asbestos products in new buildings, (2) specify work practices for removal of ACM from buildings, and (3) require the identification of asbestos in schools. There are no exposure standards for nonindustrial settings, and no regulations requiring corrective actions in buildings with ACM. 1.1 Asbestos-Containing Materials in Buildings Asbestos may be found in cement products, acoustical plaster, fireproofing textiles, wallboard, ceiling tiles, vinyl floor tiles, thermal insulation, and other materials.1 EPA surveys estimate that 31,000 schools and 733,000 federal and commercial buildings have ACM in one form or another (USEPA 1984a, 1984b). ACM has been grouped into three categories: (1) sprayed- or troweled-on materials on ceilings, walls, and other surfaces; (2) insulation on pipes, boilers, tanks, ducts, and other equipment; and (3) other miscellaneous products. (Examples of ACM are shown in Figure 1.) Material in the first two categories can be friable, that is, it can be crumbled, pulverized, or reduced to powder by hand pressure. Most ACM in the third category is nonfriable. 1 Descriptions of these and other types of products containing asbestos appear in Appendix A. 1-1 Friable materials are more likely than nonfriable materials to release fibers when disturbed or damaged. Although nonfriable ACM is of less immediate concern, it should not be ignored. Fibers will be released if nonfriable material is cut, drilled, sanded, or broken during building repairs or renovation. 1.2 Levels of Airborne Asbestos in Buildings and Other Settings Levels of airborne asbestos in the asbestos industry workplace are substantially higher than levels found outdoors or in buildings with ACM. Figure 2 shows levels measured in the three settings: asbestos insulation plants before the 1972 Occupational Safety and Health Administration (OSHA) exposure standards, schools with ACM, and outdoor urban areas.2 The range of values in each category reflects differences in location, source of asbestos, and variability in asbestos measurements. Concentrations may exceed the upper limits of these ranges for short periods if, for example, manufacturing equipment malfunctions, insulating material is pierced with a sharp object, or asbestos-coated surfaces are disturbed by the impact of a ball or similar object. Figure 2 shows that prevalent concentrations of airborne asbestos in a sample of school buildings were approximately 10 to 100 times higher than outdoors. At the same time, asbestos levels in the schools were 10,000 to 100,000 times lower than pre-1972 levels in asbestos insulation workplaces. 3 1.3 Diseases Associated with Exposure to Asbestos Much of what is known about asbestos-related diseases comes from studying workers in the various asbestos industries. Exposure to levels of airborne asbestos typical of the asbestos workplace prior to 1972 has been linked with a debilitating lung disease called asbestosis; a rare cancer of the chest and abdominal lining called mesothelioma; and cancers of the lung, esophagus, stomach, colon, and other organs. In 1972 federal exposure standards were imposed. The relationship between exposure level and health risk is complex. The potential for disease appears to be related to the physical and chemical characteristics of asbestos fibers as well as to the concentration of fibers in the air. Data on asbestos workers indicate that the risks of asbestosis, lung cancer, and mesothelioma decrease in direct proportion to a decrease in total asbestos dose. Because there is no direct information on health risks from exposure to asbestos in buildings with ACM, the risks are estimated by extrapolation from studies of asbestos industry workers (Nicholson 1984, NRC 1984, The Royal Commission of Ontario 1984). The estimates indicate that only a small proportion of people exposed to low levels of asbestos will develop asbestos-related diseases. However, combining smoking with occupational exposure to asbestos increases the lung cancer rate above the rate due to either smoking or asbestos exposure alone. Also, asbestos exposure in children is of special concern: since they have a greater remaining lifespan than adults, their lifetime risk of developing mesothelioma is greater. Avoiding unnecessary exposure to asbestos is prudent. 2 For comparison, all data are expressed in nanograms per cubic meter (ng/m 3) units. Concentrations of asbestos fibers in the air are measured in terms of either the number of fibers per unit volume (typically, fibers per cubic centimeter) or the mass per unit volume (typically, ng/m3). A nanogram is one-billionth of a gram. See Appendix B for a simple explanation of measurement units used for airborne asbestos concentrations. 3 The data in Figure 2 should be interpreted with caution. Estimated concentrations in asbestos workplaces are based on measurements of airborne fibers using the method specified by OSHA (phase contrast microscopy), while the levels in schools and outdoors were measured by a different method (transmission electron microscopy). Comparisons of measurements obtained by the two methods are based on certain assumptions (see footnote to Figure 2). Measurement of airborne asbestos fibers is a complex subject and is discussed in more detail in Section 4.1.2. 1-2