By Ed Cahill
Vice President, Asbestos Division, EMSL Analytical Inc.
On June 22, 2012 the New York State Department of Health (NY DOH) issued a guidance letter outlining its policy on asbestos testing of materials containing vermiculite. This was a clarification and guidance with respect to an earlier FAQ the department released on April 8, 2011. To summarize, any loose fill vermiculite such as Vermiculite Attic Insulation (VAI), block fill, packing material etc. must be treated as Asbestos Containing Material (ACM). No analysis is necessary and in fact no laboratory analysis results will be deemed adequate to classify this material as non ACM.
The real surprise however was that in addition to loose fill vermiculite, any building material with >10% vermiculite as a component must also be treated as ACM! Fortunately this applies to relatively few types of building materials. Unfortunately one of the sample types it does apply to is spray-on fireproofing. The implications here are great for many large building owners.
Spray on fireproofing is, as the name implies a fire proof insulation that is literally sprayed onto the structural steel of buildings to protect it in case of fire. In an intense fire this insulation can make the difference in whether a building remains standing or collapses. Asbestos was an obvious component to add to spray on insulation since it is fireproof and an excellent thermal insulator. Due to the now well understood hazards of asbestos inhalation the EPA banned the use of sprayed on insulation containing asbestos in 1973. New formulations were created after that with no asbestos deliberately added. Ironically asbestos was still often present due to asbestos contamination in the vermiculite used. The most common source of vermiculite for over 70 years was the now closed vermiculite mine in Libby Montana. Vermiculite from this mine can contain a considerable amount of asbestos, both regulated and non-regulated. Since vermiculite is only one component in common spray on insulations such as W.R. Grace’s Monokote 5 or Isolatek’s Cafco 300, the final percentage of asbestos is often determined to be <1% by a typical asbestos analysis by PLM. Other components can include gypsum, calcium carbonate, cellulose, cement and mineral wool.
With the policies outlined in the June 2012 guidance document many New York building owners are facing a new reality, including major financial implications. Spray on fireproofing that was determined to be non-detect or <1 percent asbestos (non ACM) from surveys and lab analyses performed prior to the revised NYS guidance, now would be classified as ACM (asbestos containing material) because the vermiculite content is estimated to be >10 percent!
Beyond the June 22, 2012 letter little additional guidance was provided and asbestos consultants and laboratories struggled to interpret the guidance and strive for compliance. In response to growing concerns from all corners of the industry the Department of Health issued another three page guidance letter dated July 9, 2013 which allowed for an interim testing alternative to be used on materials with >10% vermiculite. This alternative testing method is the existing NY ELAP (Environmental Laboratory Approval Program) method 198.6 Polarized Light Microscopy (PLM) method that is used for non-friable organically bound samples such as floor tiles and mastics. With this method a material with >10% vermiculite may be classified as non-ACM, but with a catch. If this alternative method is used, the following “conspicuous disclaimer” must be added to the sample report.
“This method does not remove vermiculite and may underestimate the level of asbestos present in a sample containing greater than 10% vermiculite.”
Ironically this disclaimer must be placed on the report even if the material is determined to be >1% asbestos and classified as ACM!
The guidance letter explains that this alternative method is to be used “until new testing methods are established that effectively remove vermiculite from test samples and accurately identify asbestos.”
No information is provided as to when that might happen or what that final method might look like. There are existing procedures, such as the one outlined in Analysis of Amphibole Asbestos in Chrysotile and Other Minerals by Addison and Davies (1990). These involve hazardous chemical digestions with sequential boiling in acid and then a base. These are procedures best performed in a chemistry laboratory not your typical small scale asbestos analysis laboratory.
The unfortunate consequence is a current state of uncertainty and limbo in the industry on this issue. The requirement of placing the strong disclaimer on all reports when using the alternative testing method negates the ability to technically classify the materials as non-ACM for many end users of these data. In the face of this uncertainty building owners and their consultants are taking many various approaches:
Approach 1
- Cancel or delay asbestos surveys if possible until final regulations are in place. This is likely affecting and delaying many real estate transactions.
Approach 2
- If initial analysis determines vermiculite content >10% they are stopping. The material is treated as ACM.
Approach 3
- If initial analysis determines vermiculite content >10% they are proceeding on to the alternative (additional) test method (ELAP 198.6) to determine the ASBESTOS percentage. Materials are classified as ACM or non-ACM accordingly and the disclaimer is tolerated or ignored.
Approach 4
- Approach 2 or 3 are followed for regulatory compliance and then various additional preparation and analysis steps are requested. Transmission Electron Microscopy (TEM) analysis is very often part of this process as an effort to demonstrate the use of “Best Available Technology”.
As stated previously all loose fill vermiculite including Vermiculite Attic Insulation (VAI) and block fill insulation must be treated as ACM. There are no New York approved methods for the analysis of vermiculite and none may be used to try and classify this material as non-ACM. This ELAP position is aligned with the current EPA stance that there are currently no validated and approved analytical methodologies to accurately analyze and quantitate asbestos concentrations in vermiculite. The ASTM D22 Committee is currently working on a draft method for the qualitative analysis of asbestos in loose fill vermiculite by TEM. This method will likely go to ballot by years end and could possibly be finalized in 2014.
The steps necessary for compliance with the New York State policies regarding vermiculite containing materials are outlined in the latest guidance letter as a flowchart seen below.
For all friable (can be crushed by hand pressure) building materials the process begins with NY ELAP Method 198.1 Polarized-Light Microscope Methods for Identifying and Quantitating Asbestos Bulk Samples. This method is similar in many ways to the more widely used EPA 600 PLM method used in other states. With the new policies the first step is to examine the sample for its vermiculite component.
Scenario 1 Vermiculite <10%
- If the vermiculite is determined to be ≤10% then the sample is treated like any other friable sample and analysis by method 198.1 continues in order to determine asbestos percent.
- NOTE 1: Method 198.1 and the guidance letter mandate that quantitation be performed by a point counting procedure. The point count technique can be a more accurate quantitation technique than the more common calibrated visual estimation (CVE) technique used in most circumstances in other states. But it requires a microscope slide preparation that is as close to a monolayer as possible. Due to its relatively large size vermiculite in most cases is not conducive to a good (and accurate) point count.
- NOTE 2: This critical part of the analysis is being applied unevenly from lab to lab with some labs attempting to differentiate between vermiculite and other micas that might be in the sample. The result can be large discrepancies in vermiculite estimates from lab to lab.
- Vermiculite Attic insulation (VAI) by PLM
Scenario 2 Vermiculite >10%
- If point counting by method 198.1 determines the vermiculite content to be greater than 10% this analysis is terminated (no asbestos determination is performed).
- The analyst proceeds with analysis via ELAP method 198.6 Polarized-Light Microscope Method for Identifying and Quantitating Asbestos in Non-Friable Organically Bound Bulk Samples
- This method requires special preparation steps to remove and track the weight loss of organic and acid soluble matrix material prior to analysis. It will not remove vermiculite unfortunately.
- Asbestos analysis by PLM is performed on the resulting residue. The weight loss is included in the calculation of the final asbestos percent.
- NOTE: Differentiation between the regulated and non-regulated asbestos types that are found in the common Libby vermiculite can be difficult by PLM. TEM is superior for this.
- Regardless of whether or not the material is determined to be ACM (>1%) or non ACM (<1%) the following disclaimer must be added:
“This method does not remove vermiculite and may underestimate the level of asbestos present in a sample containing greater than 10% vermiculite.”
The current uncertainty in regards to vermiculite containing materials is unfortunate and has many agencies, regulators, building owners and consultants sitting on the sidelines waiting for more clarity. Those that are proceeding are faced with inconsistent application of existing guidance and the potential that their samples may need to be re-analyzed once the “final” method is adopted.