AL Asbestos Abatement cheat sheet

Negative pressure enclosures are maintained at approximately -0.02 inches of water column relative to adjacent areas, verified with a differential pressure monitor.

Critical barriers seal all openings (HVAC, windows, doors, electrical) in the work area before abatement begins; decontamination unit has clean, shower, and equipment rooms in series.

Wet methods: saturate ACM with amended water (water plus a wetting agent) before and during removal to suppress fiber release; keep ACM wet through bagging.

Regulated area air enters through the decon unit and exits through HEPA filtration; exhaust air must pass HEPA filters before release.

Glove bag work is limited to small, localized removal on pipe runs; seal bag to pipe, remove ACM inside bag, and never exceed bag capacity.

Encapsulation coats ACM to seal fibers in place; enclosure installs a rigid airtight barrier over ACM - neither removes the material, so both are management options, not abatement.

Waste: double-bag or wrap in 6-mil (or greater) leak-tight containers, label with required warning, and transport in covered vehicles.

Daily cleanup and a final visual inspection by the supervisor precede clearance air sampling; visible debris must be removed before clearance.

NESHAP (40 CFR Part 61 Subpart M): 10-day advance written notification to the EPA (or delegated state) before demolition or renovation that will disturb a threshold quantity of regulated asbestos-containing material.

Threshold quantity under NESHAP is 260 linear feet on pipes, 160 square feet on other components, or 35 cubic feet of RACM off facility components.

NESHAP defines RACM (regulated asbestos-containing material) and requires wetting, careful handling, and no visible emissions during removal, transport, and disposal.

Asbestos Hazard Emergency Response Act (AHERA) governs schools: accredited inspectors, management plans, and periodic reinspection; applies to public and private K-12 buildings.

Asbestos School Hazard Abatement Reauthorization Act (ASHARA) extends accreditation/training requirements to public and commercial building abatement workers and supervisors.

OSHA 29 CFR 1926.1101 (construction) and 1910.1001 (general industry) set exposure limits, training, medical surveillance, and work practice requirements.

Permissible exposure limit (PEL) is 0.1 fibers per cubic centimeter (f/cc) as an 8-hour time-weighted average; excursion limit is 1.0 f/cc over 30 minutes.

State and local rules can be stricter than federal; confirm jurisdiction-specific notification timing, licensing, and air-clearance criteria before work begins.

Asbestos fibers cause asbestosis (fibrosis), lung cancer, and mesothelioma; risk increases with cumulative dose and time since first exposure.

Mesothelioma is strongly associated with asbestos and can occur at low exposures; latency is typically 20-40 years, so effects appear long after exposure.

Smoking multiplies lung cancer risk in asbestos-exposed workers (synergistic), though it is not linked to mesothelioma causation.

Respiratory protection selection follows assigned protection factors: half-mask APR (APF 10), full-face APR (APF 50), powered air-purifying respirator (APF 25-1000 by type), supplied-air/SCBA for higher protection.

Fit testing (quantitative or qualitative) is required before respirator use and annually thereafter; users must be medically evaluated and trained.

Personal protective equipment: disposable coveralls, hood, boots, gloves; remove contaminated PPE in the equipment room before showering in the clean room.

Medical surveillance includes baseline and periodic exams, respiratory questionnaire, and spirometry for workers above exposure/usage triggers.

Decontamination sequence: equipment room (remove outer PPE) → shower → clean room (dress in street clothes); never reverse the flow.

Personal air samples are collected in the breathing zone (collar area) with calibrated pumps; results compared to PEL (0.1 f/cc TWA) and excursion limit (1.0 f/cc, 30 min).

Phase contrast microscopy (PCM) is the standard field method for fiber counts; it cannot distinguish asbestos from other fibers, so it is used with work-practice controls.

Transmission electron microscopy (TEM) identifies and counts asbestos fibers specifically; commonly used for final clearance in schools under AHERA.

Clearance criteria: AHERA requires TEM analysis with fiber counts below specified limits and a thorough visual inspection showing no debris.

Air sampling pumps must be pre- and post-calibrated with a primary standard (e.g., bubble burette) to establish flow rate and sample volume.

Sample volume = flow rate × sampling time; fiber concentration = fibers counted / (fields counted × field area × volume) per the PCM counting rules.

Aggressive sampling (fans, blowers) disturbs settled dust to verify enclosure cleanliness before clearance; performed after final cleaning.

Background/area samples establish baseline fiber levels; compare work-area and decon samples to background to detect fiber migration.