DE Asbestos Abatement key terms

Asbestos material that can be crumbled, pulverized, or reduced to powder by hand pressure when dry. Friability drives how easily fibers become airborne and therefore how strictly the material must be handled.

Asbestos-containing material that resists being crumbled or powdered by hand pressure. Examples include asbestos cement siding, floor tile, and roofing felt, which release fibers mainly when cut, sanded, or broken.

Regulated Asbestos-Containing Material. Under NESHAP, this covers friable ACM, Category I and II non-friable ACM that has become friable or will be sanded/ground/cut, and non-friable ACM with a high asbestos content that is damaged.

Non-friable asbestos-containing material that contains more than 1 percent asbestos and includes packings, gaskets, resilient floor coverings, and asphalt roofing products. It becomes regulated when sanded, ground, cut, or damaged.

Non-friable asbestos-containing material other than Category I, such as asbestos cement sheet, pipe, and shingle. It is regulated when it becomes friable or is expected to be crumbled or pulverized during demolition or renovation.

Any material or product that contains more than 1 percent asbestos by weight, as determined by an accredited inspector using polarized light microscopy or an equivalent method. The 1 percent threshold is the regulatory trigger for most requirements.

Material that has not been sampled or analyzed but must be treated as asbestos-containing until proven otherwise. Renovation and demolition rules require presuming suspect materials are ACM if they are not inspected.

A building material that, because of its type, use, or age, may contain asbestos. Inspectors must identify and sample all suspect materials before renovation or demolition disturbs them.

A complete walk-through of a facility by an accredited inspector to locate and assess all suspect asbestos-containing materials, including concealed spaces, before renovation or demolition work begins.

Collecting physical samples of suspect material for laboratory analysis to determine whether asbestos is present and in what percentage. Sampling must follow accepted procedures to avoid cross-contamination and represent the material accurately.

Polarized Light Microscopy. The standard laboratory method for identifying asbestos fibers in bulk samples by their optical properties. It reports fiber type and percentage, with gravimetric or point-counting methods used for low concentrations.

A more precise PLM analysis in which the microscopist counts fibers at hundreds of grid points to estimate asbestos percentage. It is used when the initial estimate is near the 1 percent regulatory threshold.

A person who has completed an approved asbestos inspection course and passed the required exam, qualified to identify and assess ACM and collect bulk samples. Accreditation must be maintained through refresher training.

A progressive, irreversible lung disease caused by inhaling asbestos fibers. Scar tissue builds up in the lungs, reducing elasticity and gas exchange, and symptoms such as shortness of breath typically appear years after exposure.

A rare cancer of the thin membranes lining the chest, abdomen, or heart, strongly associated with asbestos exposure. It has a long latency, often decades, and can occur after relatively low cumulative exposures.

A malignant tumor of the lung associated with asbestos inhalation, with risk rising sharply in people who also smoke. It is one of the major causes of death attributed to occupational asbestos exposure.

The time between first asbestos exposure and the appearance of disease, commonly 10 to 40 years or more. Because of this delay, current illness often reflects exposures that occurred decades earlier.

Inhalation or ingestion of airborne asbestos fibers. Risk increases with the concentration of fibers in air, the duration and frequency of exposure, and the time since exposure began.

Microscopic, needle-like mineral strands that can remain suspended in air for long periods and penetrate deep into the lungs. Their size and durability make them difficult for the body to clear.

Personal protective equipment, such as a fitted half-face or full-face respirator with appropriate filters, worn to reduce inhalation of airborne fibers. It requires fit testing, medical clearance, and training to be effective.

A sealed enclosure, often of plastic sheeting and tape, built around the work area to prevent asbestos fibers from escaping. It includes critical barriers at openings and is maintained under negative pressure during abatement.

A condition in which air pressure inside the containment is lower than outside, so air flows inward and fibers are kept from escaping. It is maintained with HEPA-filtered negative air machines and monitored with gauges.

High-Efficiency Particulate Air filter rated to capture at least 99.97 percent of particles 0.3 microns in diameter. It is required on vacuums and negative air machines used in abatement to trap asbestos fibers.

A temporary seal, usually plastic sheeting and tape, placed over doors, windows, vents, and other openings to isolate the work area and prevent fiber migration. It is installed before abatement begins and removed last.

A three-stage enclosure with a clean room, shower, and dirty room that workers pass through when entering and leaving the containment. It prevents fibers from being carried out on clothing or skin.

Disposable coveralls, gloves, foot coverings, and respirators worn during abatement to protect the worker from fiber contact. PPE must be removed and disposed of properly before leaving the work area.

A trained and accredited individual who removes, encapsulates, or encloses asbestos-containing material under supervision. Accreditation requires approved training and periodic refresher courses.

The person who directs abatement work and ensures compliance with work practices, safety requirements, and regulations on site. Supervisors must complete an approved course and maintain accreditation.

A business licensed or certified to perform asbestos removal and related work. It must meet state or local licensing requirements, carry insurance, and employ accredited workers and supervisors.

National Emission Standards for Hazardous Air Pollutants. The federal rules under the Clean Air Act that govern asbestos handling during demolition, renovation, and waste disposal, including notification and emission controls.

A written notice submitted to the appropriate air quality agency before starting demolition or renovation that will disturb threshold amounts of asbestos. It identifies the site, owner, contractor, and amount of RACM.

A required filing to the air quality agency before renovation work that will disturb regulated asbestos-containing material above the regulatory threshold. It must be submitted within the required time before work begins.

A tracking document that accompanies asbestos waste from the generator through transport to the disposal site. It documents quantities, dates, and handlers and must be retained and reconciled after disposal.

Placing removed asbestos debris in sealed, leak-tight, labeled containers, usually heavy-duty bags or drums, before transport. Containers must be wetted and sealed to prevent fiber release during handling.

A landfill or facility permitted to accept asbestos-containing waste material. Waste must be delivered to an approved site that follows required covering and handling practices.

Collecting and analyzing air samples to measure airborne fiber concentrations during and after abatement. It verifies that containment is working and that clearance levels are met before reoccupancy.

The final verification step after abatement in which air samples confirm fiber levels are below the required limit and the work area is visually clean. Reoccupancy is allowed only after clearance is achieved.

Treating asbestos material with a sealant that penetrates or coats it to bind fibers and reduce release. It is an alternative to removal but does not eliminate the asbestos hazard.

Building a permanent airtight barrier around asbestos-containing material so it is not disturbed. Unlike encapsulation, it does not alter the material itself but isolates it from the occupied space.

A permit issued by a state or local agency authorizing a specific asbestos abatement or renovation project. It typically requires submission of notification, project plans, and contractor credentials before work starts.