Asbestos PLM Bulk Sampling
Source: How to Manage Asbestos in School Buildings—EPA 910-B-96-001
Note: While this guide recommends common practices, other requirements might vary by state and/or agency.
The initial inspection to identify all the ACBM in a building begins with locating and listing all “homogeneous areas” of material that are suspected to contain asbestos. A “homogeneous area” is an area of surfacing material, thermal system insulation, or miscellaneous material that is uniform in color and texture. Suspected ACBM in a homogeneous area or functional space must then be treated as ACBM unless samples are taken and the sample analyses show the material to be non-asbestos. “Functional space” means a room, group of rooms, or homogeneous area designated by a person accredited to prepare management plans, design abatement projects, or conduct response actions.
Interior materials suspected of containing asbestos must be categorized as one of the following three types according to EPA:
Note: Batt, blanket, and blown-in insulation should be placed in one of the above categories according to use. Once a material is classified as a particular type, the inspector should identify areas where the materials are all of one type. EPA suggests that wings or additions added to a building should not be considered homogeneous with the original structure. Building materials used in different buildings should not be considered homogeneous. If there is any reason to suspect that materials might be different, even if they appear similar, they should be assigned to separate homogeneous areas, and if it is determined that sampling is needed, such materials should be sampled separately. It is important that the inspector correctly identify all homogeneous areas in the inspection report.
Under the AHERA Rule, all material suspected to be ACBM must be assumed to be ACBM unless:
The following table shows the number of samples required to be collected from each type of homogeneous area to meet the AHERA regulation requirements.
Bulk Sampling Requirements
Type of Material |
Samples Required |
Friable Surfacing Material |
|
|
3 |
|
5 |
|
7 |
Thermal System Insulation (TSI) |
|
|
3 |
|
1 |
|
Sample in a manner sufficient to determine if material is or is not ACBM* |
Note: The regulations do not indicate how many samples are required to meet the "in a manner sufficient to determine." But it is recommended that a minimum of three samples be taken from any homogeneous area to prove that a material does not contain asbestos. However, the designation of ACM for a homogeneous area based on one positive bulk sample result is acceptable. It is recommended that all samples taken always be analyzed, since one sample analysis is rarely representative of a homogeneous area.
*EPA recommends that three samples be taken to meet this requirement
Once all of the ACBM in a building has been identified, one must perform a physical assessment of all TSI and friable material. The physical assessment of ACBM involves classifying the material into one of the following seven Physical Assessment Categories:
The physical assessment may include the following considerations:
Because the physical assessment is used to determine which response actions will be chosen to manage the asbestos, proper identification and assessment of ACBM are vital to the effective implementation.