Asbestos-Containing Materials and Building Systems
ACM and building-systems questions test whether you can classify materials by type, friability, and regulatory category before you plan work.
Material categories
- Surfacing materials are sprayed or troweled onto surfaces: fireproofing, acoustic plaster, decorative texture.
- Thermal system insulation (TSI) covers pipes, boilers, tanks, and ducts: block, batt, wrap, and cement.
- Miscellaneous materials include floor tile and mastic, ceiling tile, joint compound, gaskets, roofing, and transite.
A material is ACM at greater than 1% asbestos as determined by polarized light microscopy (PLM). Friability is the tendency to crumble under hand pressure.
Non-friable categories
- Category I: resilient floor covering, asphalt roofing, packings, gaskets.
- Category II: all other non-friable ACM, such as asbestos-cement siding. Category I and II materials become regulated as RACM if they are sanded, ground, cut, or abraded.
Worked example
A 1972 school has spray-applied fireproofing on beams, pipe insulation, 12-inch floor tile with black mastic, and ceiling tile. The fireproofing is friable surfacing material; the pipe insulation is TSI; the tile and mastic are Category I non-friable. Each homogeneous area must be sampled and characterized separately-one floor-tile result does not classify the mastic or the ceiling tile.
Traps
- Treating “non-friable” as “not regulated.”
- Letting one sample represent several homogeneous areas.
- Forgetting mastic or joint compound.
- Assuming a building date automatically proves or disproves ACM.