4.1 The determination of contact pH can be used as a simple and fast measurement that can allow activated carbon producers and users to have a standard method for assessing the effect various carbons will have on the initial pH of the water in contact with the carbon. It has been determined that there is a bias between this method and Test Method D3838; they are not equivalent.

1.1 This method is to be used in the determination of the pH of water on initial contact with activated carbon. This test method is not meant as a replacement for Test Method D3838 and may give a different value.

1.2 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.