MT Asbestos Abatement key terms

Any material or product that contains more than one percent asbestos by weight, determined by polarized light microscopy or an accepted equivalent method, and therefore subject to regulation as asbestos material.

Material assumed to contain asbestos until sampling and laboratory analysis prove otherwise, typically applied to thermal system insulation and surfacing materials in buildings constructed before the applicable cutoff date.

Category I or Category II nonfriable asbestos material that has become crumbled, pulverized, or reduced to powder by the forces expected to act on it during demolition or renovation handling.

Describes material that can be crumbled, pulverized, or reduced to powder by hand pressure when dry, the property that most strongly determines the potential for airborne fiber release.

Describes asbestos material that cannot be crumbled, pulverized, or reduced to powder by hand pressure when dry, so fibers are bound in a matrix and release is limited unless the material is disturbed mechanically.

Nonfriable asbestos material that contains asbestos bound in asphalt, resin, or rubber, such as roofing felt, shingles, and some gaskets, and that is regulated differently from surfacing and thermal system materials.

Nonfriable asbestos material other than Category I, including products such as asbestos cement sheeting and some wallboard, which becomes regulated when it is sanded, ground, cut, or abraded.

Material sprayed, troweled on, or otherwise applied to surfaces for acoustical, fireproofing, or decorative purposes, such as sprayed ceiling texture and fireproofing on structural steel.

Material applied to pipes, fittings, boilers, tanks, ducts, or other structural components to prevent heat loss or gain, or to reduce condensation, and commonly a source of significant fiber release.

Interior building material on structural components, structural members, or fixtures that is neither surfacing material nor thermal system insulation, such as floor tile, ceiling tile, and mastic.

A physical portion of material collected in the field for laboratory analysis to determine asbestos content, collected in a way that represents the material and preserves its integrity.

The primary laboratory method for identifying asbestos in bulk building materials, using refractive index, birefringence, and other optical properties of fibers to estimate type and percentage.

A quantitative microscopy technique in which the analyst identifies particles at a grid of points across a prepared slide, used to refine the estimated asbestos percentage when results are near a regulatory threshold.

A light microscopy method used to count airborne fibers collected on filters, which counts all respirable fibers and does not distinguish asbestos from other fiber types.

A high-magnification method that identifies asbestos fibers by structure and elemental composition, required for clearance air monitoring in many abatement projects because it distinguishes asbestos from other fibers.

The collection and analysis of airborne samples to measure fiber concentration during abatement, to document employee exposure, or to establish that an area is safe for reoccupancy.

An airborne sample collected in the breathing zone of a worker using a calibrated pump worn on the body, used to determine individual exposure for comparison with permissible exposure limits.

The legally enforceable maximum airborne concentration of asbestos to which a worker may be exposed over an eight-hour time-weighted average, established by the occupational safety authority.

A short-term exposure ceiling that limits the average airborne asbestos concentration over a brief sampling period, protecting workers from peaks that an eight-hour average would not capture.

An exposure value calculated by averaging measured concentrations over the duration of a work shift, used to compare a worker's exposure against an eight-hour occupational limit.

Air sampling performed after abatement and cleaning are complete, inside the containment, to confirm that fiber levels have fallen to the required background or threshold level before reoccupancy.

A close examination of the work area, conducted after cleaning and before clearance sampling, to confirm that no visible dust, debris, or residue remains on surfaces.

Any measure or set of measures designed to permanently eliminate asbestos hazards, including removal, enclosure, encapsulation, and the cleanup of associated dust and debris.

Treatment of asbestos material with a sealant that coats or penetrates the material to bind fibers together and prevent release, without removing the material from the building.

Construction of an airtight, rigid barrier around asbestos material to prevent fiber release and isolate the material from occupied space, without altering the material itself.

The physical detachment and taking away of asbestos material from a building, the most common abatement method and the one that generates the greatest potential for fiber release.

A sealed enclosure of plastic sheeting and framing erected around a work area to prevent asbestos fibers from migrating to occupied spaces during abatement activities.

A condition in which air pressure inside a containment is kept lower than in surrounding areas, so air flows inward and any leakage carries fibers into the work area rather than out.

A filter rated to remove at least 99.97 percent of airborne particles at the most penetrating particle size, used in vacuums and air scrubbers to capture asbestos fibers.

A portable machine that draws air through HEPA filters to remove airborne particles and, in containment work, helps maintain negative pressure and clean the air.

A containment element whose failure would allow fibers to escape to an uncontrolled area, such as a doorway seal or a plastic wall joint, and which therefore receives special inspection attention.

The sequence of cleaning steps and facilities that workers and waste pass through to remove asbestos contamination before leaving the regulated work area.

A connected series of chambers, typically a dirty room, a shower, and a clean room, that workers use to remove contamination from themselves and their equipment when leaving the work area.

A sealed plastic bag with built-in gloves and an access opening, used to remove small amounts of asbestos material from pipes or components while keeping the work enclosed.

An abatement technique in which material is thoroughly wetted with amended water before and during disturbance to suppress fiber release and keep dust down.

Water mixed with a surfactant that lowers surface tension, allowing it to penetrate asbestos material more effectively and reduce airborne fiber release during wet removal.

The written set of policies, procedures, responsibilities, and recordkeeping requirements an organization uses to manage asbestos hazards, ensure regulatory compliance, and protect building occupants and workers.

A site-specific document describing locations and condition of asbestos material, response actions, and procedures for preventing disturbance, required for certain buildings under asbestos regulations.

An ongoing program of work practices, training, and periodic surveillance intended to prevent asbestos fibers from being released in buildings where material is left in place.

Required instruction that gives workers the knowledge and skills to recognize asbestos hazards, follow safe work practices, and use protective equipment appropriate to their assigned tasks.