This test method covers the determination of the water-soluble acidity or alkalinity of paper. It may be applied to writing, printing, and sized industrial paper but is not intended for testing electrical insulating papers nor those containing alkaline fillers or coatings such as casein or calcium carbonate. 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.