SAMPLING REQUIREMENTS FOR DRYWALL JOINT COMPOUND
EPA Regulations for Asbestos Drywall
EPA regulations for asbestos are prescribed to protect general human occupant health and the environment.
Under a 1994 Ruling, the sample can be composited and the asbestos content (percentage) of the wallboard system as a whole can be used for asbestos-containing material determination.
Where non-asbestos drywall can be determined to be well over twice the thickness of the joint compound not exceeding 2%, no re-analysis is required as it can be determined that the composite result would not exceed 1% asbestos.
Similarly, typical thin layers of joint compound not exceeding 1/4th of the drywall thickness containing up to 5% asbestos will not exceed the 1% threshold for a composite result.
If desired, the composite result can be determined by additional laboratory analyses rather than inference and this is recommended when additional assurances are needed for regulatory or recordkeeping purposes.
EPA based the decision to exempt ACM joint mud wallboard circumstances based on practical enforcement issues rather than epidemiological data stating the difficulties in quantifying all the joints and nail holes in a wall system to determine if the 160 sq.ft. threshold has been exceeded. EPA did not want the associated large volumes of non-ACM drywall going to asbestos landfills unnecessarily.
OSHA
OSHA regulations for asbestos are prescribed to protect workers who have hands-on or nearby exposures to asbestos in their workplace. Unlike EPA’s rule allowing compositing, the asbestos-containing material designation is unchanged for OSHA regulation purposes.
The drywall joint compound and drywall are treated as separate materials so the 2% asbestos joint compound remains a regulated asbestos-containing building material. Disturbance or removal of asbestos joint compound is considered OSHA “Class II work” (OSHA has defined four types of work ranging from Class I for the highest risk work to Class IV for the lowest risk work. The most stringent controls and training requirements apply for Class I and they are proportionately reduced for the lower Classes of work).
Therefore, to comply with OSHA requirements, asbestos drywall joint compound disturbance/removal must be performed by renovation contractors that have OSHA Class II training and utilize the prescribed Class II methods or by an asbestos abatement contractor using Class II (or better work) practices. It can be inferred then that non-removal practices such as demolition of an entire structure, which does not involve direct worker disturbance, would not require abatement to comply with OSHA requirements.
Letter to OSHA
You refer to the definition of "surfacing material" at 29 CFR 1926.1101(b) in the OSHA construction asbestos standard which reads:
"Surfacing material" means material that is sprayed, troweled-on or otherwise applied to surfaces (such as acoustical plaster on ceilings and fireproofing materials on structural members, or other materials on surfaces for acoustical, fireproofing, and other purposes).
Because the definition seems open-ended as to the purpose for applying material to a surface, it appears to you that since joint compound is applied in a manner similar to troweling it fits the definition of surfacing material. You note that the OSHA National Office has stated that joint compound is not "surfacing material", however. You request clarification of how OSHA reaches this conclusion. Moreover, you note that OSHA states in the letter dated April 28, 1997, to Mr. Gary Thibodeaux with National Service Cleaning Corporation, Orange, Texas, that joint compound is finishing material and not surfacing material. You ask what is meant by "finishing material."
OSHA reaches the conclusion that joint compound is not "surfacing material" by considering the definition of "Class II asbestos work" and analyzing the preamble to the 1994 revision of the asbestos standards.
The definition reads:
"Class II asbestos work" means activities involving the removal of ACM which is not thermal system insulation or surfacing material. This includes, but is not limited to, the removal of asbestos-containing wallboard, floor tile and sheeting, roofing and siding shingles, and construction mastics.
Note that removal of asbestos-containing wallboard is an activity involving the removal of asbestos-containing material (ACM) which is not surfacing material. In actuality, the wallboard itself seldom contains asbestos. The asbestos is usually in joint compound, spackling compound, and tape used to produce a smooth wall surface. Therefore, joint compound is by definition not surfacing material.
The preamble relates that surfacing material is material that presents "high risk." This means it is material that is easily caused to release airborne asbestos because the fibers are loosely bound. OSHA believes that the fibers in joint compound are too tightly bound for the compound to belong in the "high risk" category.
As to your question concerning "finishing material," OSHA has not defined the term with regard to its relationship to the asbestos standards because it has no special application in the standards. The term was used in the letter to which you referred to mean material that is used to fill the cracks between adjacent wallboard panels to produce a smooth wall surface.
DRYWALL JOINT COMPOUND ASBESTOS BAN
In 1977, the Consumer Products Safety Commission banned asbestos in joint compounds and drywall tape. However, these products may still have been used until 1980 or later from the oversupply that had been purchased prior to the ban. As a result, buildings constructed before 1990 may still contain asbestos in drywall. Please understand that this ban does not remove the requirement for testing prior to renovation or demolition. State Law still requires sampling of ALL materials reguardless of age and MSDS. Brand new homes 2023 when renovated STILL NEED ASBESTOS TESTING!!! Remember, the EPA prohibited manufature companies from producing more ACM. Yet, legacy uses are not banned. Legacy uses of asbestos include those already in use; it does not include new uses or imports.
Today, manufacturing the following asbestos products is prohibited. Yet, you may still come across them in older vehicles, houses, and structures. However, testing samples of material by a certified laboratory is the only way to reveal contamination and sampling is still REQUIRED by LAW reguardless of age.
Banned asbestos products:
Read our Blog on Products With Asbestos to learn more.