Purple Book (Guide for Controlling ACM in Buildings) Part 17 PDF

Water can dislodge, delaminate, or disturb friable asbestoscontaining materials that are otherwise in good condition and can increase the potential for fiber release by dissolving and washing out the binders in the material. Materials which were not considered friable may become friable after water...

Water can dislodge, delaminate, or disturb friable asbestoscontaining materials that are otherwise in good condition and can increase the potential for fiber release by dissolving and washing out the binders in the material. Materials which were not considered friable may become friable after water has dissolved and leached out the binders. Water can also act as a slurry to carry fibers to other areas where evaporation will leave a collection of fibers that can become suspended in the air. Inspect the area for visible signs of water damage, such as discoloration of or stains on the asbestos-containing material; stains on adjacent walls or floors; buckling of the walls or floors; or areas where pieces of the asbestos-containing material have separated into layers or fallen down, thereby exposing the substrate. Close inspection is required. In many areas, staining may occur only in a limited area while water damage causing delamination may have occurred in a much larger area. In addition, the water damage may have occurred since the original inspection for friable material, causing new areas to become friable and require a reinspection. Delamination is particularly a problem in areas where the substrate is a very smooth concrete slab. Check to see if the material “gives” when pressure is applied from underneath. H.2 Potential for Disturbance or Erosion H.2.1 Factor 4: Air Plenum or Direct Airstream An air plenum exists when the return (or, in rare cases, conditioned) air leaves a room or hall through vents in a suspended ceiling and travels at low speed and pressure through the space between the actual ceiling and the suspended ceiling or ducts. The moving air may erode any asbestos-containing material in the plenum. In evaluating whether an air plenum or direct airstream is present, the inspector must look for evidence of ducts or cavities used to convey air to and from heating or cooling equipment or the presence of air vents or outlets which blow air directly onto friable material. A typical construction technique is to use the space between a suspended ceiling and the actual ceiling as a return air plenum. In many cases, the tiles in the suspended ceiling must be lifted to check if this is the case. Inspection of the air handling or HVAC equipment rooms may also provide evidence (such as accumulated fibers) of the presence of this material in the plenums. Special attention should be paid to whether frequent activities (such as maintenance) disturb the material in the plenum. It is also important to check for evidence that the material is being released or eroded (i.e., has it deteriorated or been damaged so that the material is free to circulate in the airstream?). H.2.2 Factor 5: Exposure, Accessibility, and Activity These three considerations are highly interrelated and have been combined into a single factor. In general, for a site to show a high potential for disturbance, it must be exposed (visible) and accessible, and be located near movement corridors or subject to vibration. The amount of asbestos-containing material exposed to the area occupied by people will contribute to the likelihood that the material may be disturbed and determines whether the fibers can freely move through the area. An asbestos-containing material is considered exposed if it can be seen. For a material not to be exposed, a physical barrier must by complete, undamaged, and unlikely to be removed or dislodged. An asbestos-containing material should be considered exposed if it is visible, regardless of the height of the material. If the asbestos-containing material is located behind a suspended ceiling with movable tiles, a close inspection must be made of the condition of the suspended ceiling; the likelihood and frequency of access into the suspended ceiling, and whether the suspended ceiling forms a complete barrier or is only partially concealing the material. Asbestos-containing material above a suspended ceiling is considered exposed if the space above the suspended ceiling is an air plenum. Suspended ceilings with numerous louvers, grids, or other open spaces should be considered exposed. If friable asbestos-containing material can be reached by building users or maintenance people, either directly or by impact from objects used in the area, it is accessible and subject to accidental or intentional contact and damage. Material which is accessible is likely to be disturbed in the future. Height above the floor is one measure of accessibility. However, objects have been observed embedded in ceilings 25 feet or more high. Nearness of the friable asbestos-containing material to heating, ventilation, lighting and plumbing systems requiring maintenance or repair may increase the material’s accessibility. In addition, the activities and behavior of persons using the building should be included in the assessment of whether the material is accessible. For example, persons involved in athletic activities may accidentally damage the material on the walls and ceilings of gymnasiums with balls or athletic equipment. To become fully aware of occupants’ use of the building, the inspector should consult with building staff or personnel. When assessing activity levels, consider not only the movement caused by the activities of people but also movement from other sources such as high vibration from mechanical equipment, highways, and airplanes. Another source of vibration is sound, such as music and noise, which sets airwaves in motion at certain frequencies. As these sound waves impact on asbestos-containing material, they may vibrate the material and contribute to fiber release. Therefore, more fibers may be released in a music practice room or auditorium than in the rest of the building. The amount of activity of the occupants can best be described by identifying the purpose of the area as well as estimating the number of persons who enter the area on a typical day. H.2.3 Factor 6: Change in Building Use A planned change in the use of the building from, for example, a junior to a senior high school may imply significant changes in the potential for erosion or disturbance. Of particular note is the for damage from balls to previously increased potential The addition of machinery inaccessible ceilings in gymnasiums. (such as dust collectors in wood or metal shops) to a school or office building may introduce vibrations which, again, may be a future cause of concern. The inspector should exercise judgement and draw on experience in evaluating the likely effect of such changes. Appendix I. Example Building Inspection Form Room: Building: Evaluator: Coated Area: Sample Number(s) : Address: Phone No. : Ceiling Wall(s) Structural Members Above Suspended Ceiling Pipe Lagging Boiler Insul. Other: Type of Ceiling: Suspended Metal Lath Concrete 3 Coat Plaster System Suspended Lay-In Panels Concrete Joists and Beams Tile Corrugated Steel Steel Beam or Bar Joists Metal Deck ft. Ceiling Height: Ceiling Shape: Flat Dome Other (draw) : Folded Plate Barrel Rough Concrete Smooth Concrete Masonry Plasterboard Other: sq. ft. Amount of Friable Material in Area being Evaluated: Fibrous Granular/Cementitious Concrete Like Description (hard) of Coating: (highly friable) (soft) Type of Wall (If Coated): No Is thickness uniform: Yes inch(s) Thickness: Yes No Coating debris on Floor/Furniture/Work Surfaces: Curtains, expandable partitions, etc. being pulled across coating: Yes Surface Type of Lighting: No. of Lights: Concrete Type of Floor: What is above the room being Suspended Recessed Mounted Type of Heating/Cooling Systems: Wood Other: Carpet Tile evaluated? Comments: I-1 No I.1 Notes to Appendix I The need for collecting most of the information on this form is discussed in Chapter 5 (Section 5.1). The form requires one additional piece of information: the presence of curtains or expandable partitions which are pulled across asbestos-containing material. Where this situation is found, the curtains or partitions should be removed or repositioned to eliminate contact with the material, Any damage to the asbestos-containing material then can be repaired. This form was provided by Wolfgang Brandner, the Regional Asbestos Coordinator in Region VIl. I-2