In 2008, the Environmental Protection Agency (EPA) responded to a question by the New York State Department of Labor (NYSDOL) regarding the minimum number of bulk samples required for suspect asbestos-containing miscellaneous materials (see our blog post dated 6/24/08 and rebooted 07/09/22). This clarification determined that the minimum number of samples is two (2) samples for each suspect homogeneous miscellaneous materials. This clarification was determined based on a review of the EPA's Asbestos Hazard Emergency Response Act (AHERA) section 763.86 -Sampling. This section of the AHERA regulation is used by asbestos inspectors to determine the number of samples to take for each homogeneous area. However, it is important to remember when sampling joint compound and add-on material (which are miscellaneous materials) that EPA's "Sampling Bulletin 093094", requires 3 samples per homogeneous area for joint compound and 3 samples per homogeneous area of add-on material. The core of all asbestos inspections is the determination of the type of material (surfacing material, thermal system insulation, or miscellaneous material) and whether the materials are homogeneous. A homogeneous area is defined as a type of material that is uniform in color and texture (as per 763.83). Once the type of material is determined and the material is classified as a homogeneous area, then the number of samples for each area is determined.
If the suspect asbestos material is a surfacing material, the square feet of the homogeneous area is determined which provides the inspector with the minimum number of samples that shall be taken. If the homogeneous area is less than 1,000 square feet, the inspector shall take 3 samples. If the area is between 1,000 and 5,000 square feet, the inspector shall take 5 samples. When the area is over 5,000 square feet, the inspector shall take 7 samples. This is sometimes known in the industry as the 3-5-7 rule. In addition,
EPA also published "
Asbestos in Buildings: Simplified Sampling Scheme for Friable Surfacing Materials," otherwise known as the "Pink Book." This document not only describes the process for random sampling but also recommends that for surfacing materials the number of samples should be 9 per homogeneous area no matter the number of square feet.
Should the suspect asbestos material be classified as thermal system insulation then the inspector must determine if the material is a homogeneous area, a patch material, or a cement or plaster used on fittings (tees, elbows, or valves). Homogeneous areas of thermal system insulations shall require 3 samples, while each homogeneous area of patch material less than 6 linear feet or 6 square feet shall require only 1 sample. Cement or plaster used on fittings shall be sampled based on each insulated mechanical system (hot water, cold water, steam, chilled water, etc.) and shall require a minimum of 2 samples to be taken. In addition,
EPA strongly recommends that at least three samples be taken in large homogeneous areas, even when the regulations do not require it. This recommendation was published in
EPA's 700/B-92/001 A Guide To Performing Reinspections Under AHERA.Some general rules to remember when taking bulk samples is sampling should be taken in a randomly distributed manner, samples cannot be composited, and shall be submitted to laboratories accredited by the
National Voluntary Laboratory Accreditation Program (NVLAP) and, in New York State, approved
New York State Department of Health Environmental Laboratory Approval Program (
NYSDOH ELAP). Asbestos Inspectors determine a homogeneous area contains asbestos when one of the required numbers of samples contains asbestos in the amount greater than 1%. Should all the required samples taken in a homogeneous area result in asbestos amounts less than or equal to 1%, then the area does not contain asbestos as per
EPA. However, you must make sure your client is aware that under the
Occupational Safety and Health Administration (OSHA) regulation 1926.1101 these materials are still regulated as asbestos and there are specific requirements under the
OSHA regulation on handling these materials, see
OSHA's
standard interpretation letter dated November 24, 2003.
As Asbestos Inspectors we should also remember that the
American Society of Testing and Materials (ASTM) has a
Standard Practice for Comprehensive Asbestos Survey ASTM E2356-18. This standard practice has also been approved by
EPA as the method for performing asbestos surveys for the purposes of complying with the
National Emissions Standards for Hazardous Air Pollutants (NESHAPS) regulation. That regulation requires a "
thorough inspection" of the facility for asbestos and
EPA expects an owner/operator to follow the steps described in
Sections 1 through 5 and section 8 (the pre-construction survey) in the
ASTM standard. Being an Asbestos Inspector and performing an asbestos survey is not an easy task. There are a lot of different documents that you have to have knowledge about to be able to perform your task and then on top of that you must have knowledge regarding where asbestos was used in building materials.
