OK Asbestos Abatement cheat sheet

Inhalation is the primary exposure route; ingested fibers are largely excreted, but swallowing of cleared mucus can contribute to GI exposure.

Fiber dose metrics: cumulative exposure (fiber-years/mL) drives asbestosis risk; latency for asbestosis is typically 10–20 years, for lung cancer 15–30 years, and for mesothelioma 20–50 years.

Smoking multiplies lung cancer risk in asbestos-exposed workers (synergistic, roughly multiplicative), but smoking does not increase mesothelioma risk.

Asbestos types: serpentine = chrysotile (curly, most common, less biopersistent); amphiboles = amosite, crocidolite, anthophyllite, tremolite, actinolite (straight, more carcinogenic per unit dose).

Diseases: asbestosis (diffuse interstitial fibrosis, dose-related), lung cancer, mesothelioma (pleural or peritoneal), and nonmalignant pleural effects (plaques, thickening, effusion).

Fiber dimensions affecting pathogenicity: fibers >5 µm length, <3 µm diameter, length:diameter ratio >3:1 are the regulated countable fibers; thin long fibers penetrate deepest.

OSHA 8-hour TWA PEL = 0.1 f/cc; excursion limit = 1.0 f/cc over 30 minutes; these are the exposure thresholds triggering compliance actions.

Take-home exposure: fibers on clothing, hair, and shoes can be transported to family vehicles and homes; change clothes and shower before leaving the site.

NESHAP (40 CFR Part 61, Subpart M) applies to owners/operators of demolition and renovation of facilities; threshold for regulated asbestos-containing material (RACM) is 260 linear feet on pipes, 160 square feet on other components, or 35 cubic feet off facility components.

NESHAP category definitions: Friable = crumbles under hand pressure; Category I nonfriable = asphalt roofing, shingles, vinyl floor tile; Category II nonfriable = everything else nonfriable (e.g., transite, cement pipe).

RACM = friable ACM, Category I or II that will be or has been crumbled, pulverized, or reduced to powder during demolition/renovation, or Category I/II that has a high probability of becoming crumbled.

NESHAP notification: written notice to the appropriate agency at least 10 working days before demolition or renovation begins; includes start/end dates, quantity, and disposal site.

OSHA Construction Standard 29 CFR 1926.1101 covers construction, renovation, demolition, and abatement; General Industry 29 CFR 1910.1001 covers maintenance and custodial work in general industry.

OSHA exposure assessment: initial exposure monitoring required unless objective data demonstrate exposures below the PEL; periodic monitoring at least every 6 months while exposures remain at or above PEL, and quarterly if above PEL.

Oklahoma DEQ administers NESHAP and state asbestos rules; Oklahoma requires accreditation of asbestos workers, contractors, inspectors, and management planners through an approved training program, and licensing/notification through DEQ.

OSHA Class I work = removal of thermal system insulation (TSI) and surfacing ACM/PACM; Class II = removal of ACM other than TSI/surfacing; Class III = repair/maintenance likely to disturb ACM; Class IV = maintenance/custodial activities contacting ACM.

An inspection must be performed by an accredited inspector; a management planner uses inspection data to develop an O&M plan or abatement recommendation.

Bulk sampling: collect in a dust-tight container, label with sample number, date, location, and inspector; take samples in a random manner throughout each homogeneous area.

Minimum number of bulk samples per homogeneous area: 3 for surfacing material, 3 for thermal system insulation, and 2 for all other materials (per EPA 40 CFR 763 / AHERA).

A homogeneous area is material that appears uniform in color and texture; if any sample in a homogeneous area tests positive, the entire area is considered ACM until proven otherwise.

Polarized light microscopy (PLM) is the standard method (EPA Method 600/R-93/116); it identifies fiber type and estimates percentage; PLM cannot reliably quantify fibers <1% or distinguish some amphiboles without additional methods.

Point counting (400-point) improves accuracy for low-percentage samples; gravimetric or TEM methods may be used when PLM is inconclusive.

Bulk samples should be taken from material that will be disturbed, including layers and underlying material; sample all distinct layers of multi-layer systems.

Presumed asbestos-containing material (PACM) must be treated as ACM until sampled and shown negative; TSI and surfacing materials in buildings constructed before the applicable cutoff are presumed ACM.

Negative pressure enclosure: maintain at least −0.02 inches of water column relative to adjacent areas; use HEPA-filtered negative air machines sized to achieve 4 air changes per hour (ACH) in the containment.

Wet methods: saturate ACM with amended water (water plus a surfactant, e.g., 50:50 or per manufacturer) before and during disturbance to suppress fiber release; keep material wet until packaged.

Removal sequence: remove non-friable and less friable materials first; work from top down; TSI and surfacing ACM removed before substrate demolition; do not drop or throw debris.

Glove bag: a sealed bag with built-in sleeves and glove ports for small-diameter pipe removal; must be sealed to pipe, negative pressure maintained, and the bag collapsed and sealed before removal.

Local exhaust ventilation and HEPA vacuums: use HEPA-filtered vacuums for cleanup; never use ordinary shop vacuums; HEPA filters rated 99.97% at 0.3 µm.

Critical barriers: seal windows, doors, vents, and penetrations with 6-mil poly and duct tape before containment construction; containment must be airtight.

Decontamination: workers pass through a clean room → shower → equipment room sequence; equipment and waste exit through a separate decontamination unit or bag-out procedure.

Prohibited practices: dry sweeping, use of compressed air, and grinding or sanding of ACM are prohibited; high-speed abrasive cutting of ACM is prohibited unless controlled with wet methods and HEPA exhaust.

Respiratory protection selection: half-mask APR with HEPA filters for exposures up to 10× PEL; full-face APR up to 50× PEL; PAPR with HEPA up to 1,000× PEL or per assigned protection factor; supplied-air respirators for higher concentrations or IDLH conditions.

OSHA requires a written respiratory protection program, medical evaluation, fit testing, and training before respirator use; fit testing is required annually and whenever a different respirator model is used.

Fit testing: qualitative (saccharin, Bitrex, irritant smoke) or quantitative (portacount, generated aerosol); must be performed with the same make, model, and size respirator the worker will wear.

Protective clothing: disposable coveralls (Tyvek or equivalent), hood, boot covers, and gloves; tape cuffs and ankles; remove and bag contaminated clothing before leaving the work area.

Eye protection: goggles or full-face respirator to prevent eye irritation from fibers and amended water; safety glasses alone do not seal against airborne fibers.

Decontamination sequence for PPE: remove outer coveralls inside the work area, bag as waste, shower before donning street clothes; respirator removed last in the clean room after showering.

Medical surveillance: required for employees exposed above the PEL for 30 or more days per year; includes medical history, physical exam, and pulmonary function tests; chest X-ray per physician recommendation.

Respirator care: clean and disinfect after each use, store in a clean dry location, inspect before each use, and replace HEPA filters when breathing resistance increases or per manufacturer schedule.

Containment construction: use 6-mil fire-retardant polyethylene sheeting on floors, walls, and ceilings; overlap seams and seal with duct tape; install critical barriers at openings.

Negative air machines must be HEPA-filtered and exhausted outside the containment; monitor pressure differential continuously and record readings; shut down and investigate if pressure is lost.

Decontamination unit: three-stage (clean room, shower room, equipment/waste room); workers move from dirty to clean; waste moves out through the equipment room or bag-out.

Cleanup: wet wipe and HEPA vacuum all surfaces; use disposable rags and mops; do not reuse contaminated cleaning materials; bag and label all waste.

Visual inspection: containment is visually clean when no dust or debris remains; clearance air monitoring follows visual inspection and must meet the clearance criterion before reoccupancy.

Clearance criteria: final air samples must be below the clearance level (e.g., 0.01 f/cc by PCM, or per project spec); aggressive sampling may be used to disturb settled dust.

Waste packaging: double-bag or wrap in 6-mil poly, seal with duct tape, label with asbestos warning and generator information; sharp or heavy debris placed in rigid containers.

Containment removal: after clearance, remove poly sheeting carefully, misting to suppress dust; bag sheeting as asbestos waste; inspect for residual debris before final cleaning.

NESHAP waste handling: all RACM must be wetted, bagged or wrapped in leak-tight containers, and labeled with the asbestos warning and the generator's name and location.

Transport: use covered vehicles or closed containers; waste must not be visible; vehicles must be cleaned if contaminated; DOT hazardous material regulations may apply for labeling and shipping papers.

Disposal: only at an approved landfill permitted to accept asbestos waste; the landfill must be notified before delivery; disposal must be documented with a waste shipment record or manifest.

Waste shipment records: retain copies for at least 2 years (or longer per state rule); include quantity, type, date, generator, transporter, and disposal site.

On-site storage: store bagged waste in a secured, labeled area away from traffic; do not accumulate waste outside containment longer than necessary; protect from weather and vandalism.

Liquid waste: water from decontamination and amended water must be filtered (e.g., 5 µm or HEPA) before discharge to sanitary sewer; check local POTW requirements.

Prohibited disposal: do not dispose of asbestos waste in ordinary dumpsters, by open burning, or by recycling; do not compact or bale asbestos waste unless the landfill permits and equipment is designed for it.

Recordkeeping: maintain waste manifests, landfill receipts, and training records; Oklahoma DEQ may audit disposal documentation during inspections.

Personal air monitoring: sample in the breathing zone (lapel), outside the respirator; use calibrated pumps and cassettes; flow rate typically 0.5–2.0 L/min for PCM.

Phase contrast microscopy (PCM) is the standard method (NIOSH 7400) for fiber counting; it counts all fibers >5 µm, not just asbestos; TEM is used for speciation and lower detection limits.

Clearance air monitoring: after final cleaning and before dismantling containment, collect samples inside the containment; clearance level often 0.01 f/cc by PCM or per contract specification; samples analyzed by an accredited laboratory.

Aggressive sampling: use a fan or blower to disturb air during clearance sampling to ensure settled fibers are captured; required by some contracts and EPA guidance.

Calibration: calibrate sampling pumps before and after each sampling event with a primary standard (e.g., bubble burette); record pre- and post-calibration; replace pumps that fail calibration.

Chain of custody: complete for each sample; include sample ID, location, date, time, flow rate, and analyst; retain records per OSHA (30 years for exposure records) and NESHAP (2 years).

OSHA recordkeeping: exposure monitoring records must be retained for 30 years; medical records for the duration of employment plus 30 years; training records for 1 year beyond employment.

Accreditation: air samples should be analyzed by a laboratory accredited by AIHA or NVLAP; Oklahoma may require use of accredited labs for clearance and compliance samples.