Asbestos is a very versatile, naturally occurring building material that is used in many aspects of the construction industry that is regulated by the Federal Government. Unfortunately, damaged or “friable” asbestos can release very small fibers that, when inhaled, may have long-term health effects.
Pre-1980 structures slated for demolition or extensive renovations may require an Asbestos Building Inspection (ABI) in order to remain in compliance with the Clean Air Act and the National Emission Standards for Hazardous Air Pollutants (NESHAP). This is a Federal requirement that is to be enforced by your local municipality where a certified AHERA (Asbestos Hazard Emergency Response Act) Inspector meets the requirements needed. Here’s a general overview of the process:
Investigation Process
The inspector performs a systematic walk-through of all accessible / assigned designated areas. The condition, accessibility, friability, and air erosion of assorted materials are documented for each location. Suspected asbestos-containing bulk materials (ACBMs) are touched in order to determine friability. Suspect ACMs are grouped into various homogeneous groups (ie, wallboard, pipe insulation, joint compound, etc.). The number of samples collected is contingent upon the amount and the type of material encountered.
Sample Collection
- The area to be sampled is first wetted with a wetting agent, preventing the possible release of dust and fibers into the atmosphere.
- A representative portion of the material is then collected.
- The sample is placed in a plastic bag, which is sealed to prevent cross-contamination and possible release of asbestos fibers.
- The sample is labeled (name & location) and recorded on a bulk survey form.
- The area sampled is repaired with an encapsulant, joint compound, and/or duct tape (If needed).
- Sampling tools are wet cleaned after sample collection to prevent cross-contamination.
- Cleaning waste is disposed of in 6-mil asbestos waste bags.
Note: Asbestos sample collection is invasive, and structure damages are to be anticipated.
Sample Amounts
Each Homogeneous Area (HA) requires the following amount of samples:
- Surfacing Materials (SM) – 3 samples for each HA of 1000 square feet or less, 5 samples for each HA of 1000 and 5000 square feet, or 7 samples for each HA of over 5000 square feet.
- Thermal System Insulation (TSI) – 3 samples for each HA that is not assumed to be ACBM or 1 sample for each HA of patched TSI not assumed to be ACBM, if <6 feet.
- Miscellaneous – For each HA of friable and/or non-friable suspected ACBM, in a manner sufficient to determine whether or not the material is ACM.
Analytical Procedures
Analysis of bulk samples is performed by an EPA-accredited laboratory and analyzed by Polarized Light Microscopy (PLM) or Transmission Electron Microscopy (TEM), depending upon the material type and condition.
The EPA is an excellent source for all the information you ever wanted to know about asbestos. But don’t hurt yourself, as the topic and myriad of regulations can become overwhelming very quickly.