This test method pertains to the determination of sulfate sulfur in coal or coke ash.

Formerly under the jurisdiction of Committee D05 on Coal and Coke, this test method was withdrawn in October 2009.This standard is a classical gravimetric sulfate method that is sometimes improperly cited for use in contracts. In addition the Eschka's Mixture that is vital for the test method is no longer available commcercially.

Laboratory furnace temperature and furnace ventilation have an influence on SO₃ retention in laboratory ash. Consequently, sulfur in ash as determined in the laboratory cannot be assumed to be equivalent to sulfur present in the mineral matter in coal or to the retention of sulfur in ash produced under the conditions of commercial utilization.

The sulfate sulfur determined by these test methods can be used to calculate the sulfur trioxide portion of ash so that the ash content or ash composition can be reported on a sulfur trioxide free basis.

1.1 This test method pertains to the determination of sulfate sulfur in coal or coke ash.

1.2 The values stated in SI units (Practice E 380) shall be regarded as the standard.

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.