MD Asbestos Abatement key terms

A group of naturally occurring fibrous silicate minerals whose long, thin, durable fibers split lengthwise and stay airborne easily, making them respirable and capable of causing serious lung disease when inhaled.

The only serpentine asbestos mineral, with curly, flexible, rope-like fibers. It accounts for most commercially used asbestos and is the type most often found in Maryland building materials.

Straight, brittle, needle-shaped asbestos minerals including amosite, crocidolite, tremolite, anthophyllite, and actinolite. They are generally considered more potent and persist longer in lung tissue than chrysotile.

Describes material that can be crumbled, pulverized, or reduced to powder by hand pressure when dry. Friable material releases fibers readily and is regulated more strictly than nonfriable material.

A fiber thin and short enough, roughly under 3 micrometers in diameter and over 5 micrometers long, to reach the deep lung. Fiber-counting methods are designed to measure this size range.

Progressive scarring of lung tissue caused by inhaling large cumulative doses of asbestos fibers over years. It stiffens the lungs, reduces gas exchange, and can cause shortness of breath and heart strain.

A rare cancer of the thin membranes lining the chest and abdominal cavities. It is strongly linked to asbestos exposure and often appears 20 to 50 years after the first exposure.

Any building material that contains more than one percent asbestos by weight, as determined by polarized light microscopy or another approved method. This one percent threshold drives most regulatory requirements.

Under NESHAP, friable ACM, Category I nonfriable ACM that has become friable or will be sanded or ground, and Category II nonfriable ACM likely to be crumbled in a demolition or renovation.

Asphalt roofing, flooring felt, and vinyl floor tile that contain asbestos and cannot be crumbled by hand. They become regulated when sanded, ground, cut, or otherwise abraded.

The National Emission Standards for Hazardous Air Pollutants. 40 CFR Part 61 Subpart M sets work practice standards, advance notification, emission controls, and waste handling rules for asbestos during demolition and renovation.

The construction-industry asbestos standard. It sets exposure limits, monitoring duties, regulated areas, engineering controls, respiratory protection, hygiene facilities, training, and medical surveillance for asbestos construction work.

The OSHA eight-hour time-weighted average limit of 0.1 fibers per cubic centimeter for asbestos. Employers must keep full-shift exposures at or below this level and control them further where feasible.

The OSHA short-term asbestos limit of 1.0 fiber per cubic centimeter averaged over 30 minutes. No employee may be exposed above this ceiling at any point during the shift.

An individual who can identify asbestos hazards, is authorized to take prompt corrective action, and supervises the work, containment, monitoring, and worker protection at the job site.

A documented employer determination, based on objective data or prior representative monitoring, showing that employee exposures for a specific task will stay below the PEL and the excursion limit.

The Asbestos Hazard Emergency Response Act. It requires inspections, management plans, and accredited abatement work in schools and created the Model Accreditation Program and clearance air sampling framework.

The state agency that licenses asbestos contractors, accredits asbestos workers and supervisors, reviews project notifications, and enforces Maryland asbestos rules, which are often stricter than federal minimums.

Written notice filed with MDE and the EPA before a regulated asbestos project begins, usually at least ten working days ahead, stating the scope, location, dates, procedures, and contractor details.

A tight-fitting respirator covering the nose and mouth with filter cartridges. In asbestos work it typically uses P100 filters and carries an assigned protection factor of 10.

A battery-powered blower that pushes air through HEPA filters into a hood or facepiece. It reduces breathing resistance and provides protection factors of about 25 to 1,000 depending on the configuration.

The expected protection level a respirator class provides when used within a complete respiratory protection program. It sets the maximum airborne concentration in which that respirator may be worn.

A test confirming that a tight-fitting respirator seals against a specific wearer's face. Qualitative methods rely on taste or odor, quantitative methods measure leakage, and retesting is required at least annually.

A containment built of plastic sheeting and kept under slight vacuum by HEPA exhaust units so air flows inward. This prevents asbestos fibers from escaping into occupied areas of the building.

A vacuum fitted with high-efficiency particulate air filters that capture 99.97 percent of particles 0.3 micrometers and larger. It is used for surface and equipment cleaning and to filter containment exhaust air.

Work practices that keep asbestos material wet with water or amended water during removal, cutting, and cleanup so fibers stay bound and are not released into the air.

A sealed plastic bag with built-in sleeves and gloves that encloses a small section of pipe or fitting, letting a worker remove asbestos-containing material without releasing fibers into the room.

A series of connected rooms, typically a clean room, a shower, and an equipment room, that workers pass through to shed contaminated clothing and fibers before leaving the work area.

A work zone marked off by barriers and warning signs where asbestos exposure may exceed the PEL or excursion limit. Only authorized, trained, and properly protected employees may enter.

An air sample drawn from the air a worker actually breathes, using a calibrated pump and filter cassette clipped near the collar. Results are compared with the PEL.

A clearance technique that uses fans or blowers to lift settled dust into the air before sampling, so results reflect the worst realistic condition rather than an artificially clean moment.

Post-abatement sampling inside the containment to show fiber levels are below the required limit, commonly 0.01 fibers per cubic centimeter by phase contrast microscopy, before the area is released.

Waste bags or wrapping of at least 6-mil plastic, sealed and labeled as asbestos waste. Containers must stay leak-tight through handling, storage, transport, and disposal.

A NESHAP-required document tracking asbestos waste from generator through transporter to the disposal site. It must be signed, kept on file, and returned with confirmation of disposal.

A periodic health program for asbestos-exposed employees, including work history, respiratory questionnaire, physical examination, and often chest X-ray and pulmonary function testing, offered at no cost to the worker.

A confidential evaluation by a physician or other licensed health care professional, usually using a questionnaire, that must be completed before an employee is allowed to wear a respirator.

OSHA requires employers to keep employee asbestos exposure monitoring records for 30 years, while medical records must be kept for the length of employment plus 30 years.

The yearly update course required to keep asbestos worker and supervisor accreditation current, covering regulation changes, work practice review, and hands-on skills practice.