Abatement: Any measure designed to permanently eliminate lead-based paint hazards. The term includes, but is not limited to, the following:

•  The removal of lead-based paint and lead-contaminated dust.
• The permanent enclosure or encapsulation of lead-based paint.
• The replacement of lead-painted surfaces or fixtures.
• The removal or permanent covering, with pavement or concrete, of lead-contaminated soil.
• ALL preparation, cleanup, disposal, and post-abatement clearance testing activities.

The term does not include:

• Renovation, remodeling, landscaping, or other activities, when such activities are not designed to permanently eliminate lead-based paint hazards, but are designed to repair, restore, or remodel a dwelling, even though these activities may incidentally result in a reduction or elimination of lead-based paint hazards:
• Interim controls, maintenance activities, or other measures designed to temporarily (not permanently) reduce lead-based paint hazards. 
• Containment: A process to protect workers and the environment by controlling exposures to the lead-contaminated dust and debris created during abatement.

Elevated Blood Lead Level (EBL): An excessive absorption of lead that is a confirmed concentration of lead in whole blood of: Ten (10) micrograms of lead per deciliter of whole blood for one venous test; or Ten (10) micrograms of lead per deciliter of whole blood in two (2) consecutive finger stick tests.

Encapsulant: A substance that forms a barrier between lead-based paint and the environment using a liquid-applied coating; or
an adhesively bonded covering material.

Enclosure: the use of rigid, durable construction materials that are mechanically fastened to the substrate in order to act as a barrier between lead-based paint and the environment.

High efficiency particle air (HEPA): A filter capable of filtering out particles of three-tenths (0.3) micron or greater from a body of air at ninety-nine and ninety-seven hundredths percent (99.97%) efficiency or greater.

Interim controls: A set of measures designed to temporarily reduce human exposure or likely exposure to lead-based paint hazards, including:

• Specialized cleaning
• Repairs
• Maintenance
• Painting
• Temporary containment
• Ongoing monitoring of lead-based paint hazards or potential hazards
• The establishment of resident education programs

Lead-based paint: Paint or other surface coating that contains lead in an amount equal to or greater than one (1) milligram per square centimeter or five-tenths (0.5%) percent by weight.

Lead-based paint hazard: Any condition that causes exposure to lead from lead-contaminated dust, lead-contaminated soil, or lead-contaminated paint that is deteriorated or present in accessible surfaces, friction surfaces, or impact surfaces that would result in adverse human health effects as identified by the US EPA.  See below for pictures of deteriorating and chipping paint. 

Lead-contaminated dust: Surface dust in residential dwellings that contains a concentration of lead at, or in excess of, levels identified by the US EPA.
Lead-contaminated soil: Bare soil on residential property that contains a concentration of lead at, or in excess of, levels identified by the US EPA.

Lead poisoning: In the US lead poisoning is formally defined as having at least 10 micrograms of lead per deciliter of blood.  Diagnosis is by blood test: blood lead levels of 10 ug/dL or greater are dangerous to children, even if the person has no apparent symptoms. (The average level of lead, for people ages 1 to 70, is 2.3 micrograms.)  The lead may come, for example, from lead-containing paint, leaded gasoline, etc. Lead was used in household paint until 1978 and was also found in leaded gasoline, some types of batteries, water pipes, and pottery glazes. Lead paint and pipes are still found in many older homes and lead is sometimes also found in water, food, household dust and soil. Lead can be a workplace hazard for people in certain occupations.

Risk assessment: An on-site environmental investigation to determine the existence, nature, severity, and location of lead-based paint hazards.