ASTM G91-11

1.1 This practice covers a weighted average effective SO₂ level for a 30-day interval through the use of the sulfation plate method, a technique for estimating the effective SO₂ content of the atmosphere, and especially with regard to the atmospheric corrosion of stationary structures or panels. This practice is aimed at determining SO₂ levels rather than sulfuric acid aerosol or acid precipitation.

1.2 The results of this practice correlate approximately with volumetric SO₂ concentrations, although the presence of dew or condensed moisture tends to enhance the capture of SO₂ into the plate.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.