Rationale: This revision to standard C22 is being proposed to satisfy the requirements of H.R. 4212, the Drywall Safety Act of 2012 (the Act), which mandates the creation of a test method that would evaluate and set limits for the sulfur content of drywall. Another part of this Act required enhanced labeling requirements for drywall, which has been completed with a revision to C1264 in November 1, 2011. A copy of the Act is available as a supporting document in the Committee Documents area. Neither the act nor ASTM C11 provides a definition of the term drywall, thus, for the purpose of this revision to ASTM C471 Test Methods and other product standards, drywall will be construed to be equivalent to the generic term, gypsum panel products, as published in ASTM C1110a. Consultants for the Consumer Products Safety Commission (CPSC) identified an allotrope of elemental sulfur, known as S8, to be present in drywall products that exhibit the so-called Chinese drywall syndrome where a corrosive sulfur compound is emitted from the drywall that attacks various reactive metals, primarily copper. The maximum level of S8 in drywall was recommended to be 5 mg/Kg in the cover letter to ASTM C11.01. The substantiation for this level is presented in the Committee Documents area. Because gypsum is used in all gypsum drywall products, C22 was selected to present the S8 limit. The limit is presented in paragraph 4.3 as being limited to gypsum panel products. Revisions to product standards that do not reference C22 as the gypsum specification will also be requested. The test method proposed by the CPSC to identify S8 is being proposed under separate ballot action.
Keywordscalcium sulfate; gypsum; Gypsum products--specifications ;
Draft Under Development