5.1 Activity as measured by this test method is basically a measure of the pore volume of the activated carbon sample. This test method is therefore a means of determining the degree of completion of the activation process, hence a useful means of quality control for gas-phase activated carbons. This activity number does not necessarily provide an absolute or relative measure of the effectiveness of the tested carbon on other adsorbates, or at other conditions of operation.

1.1 This test method covers the determination of the activation level of activated carbon. Carbon tetrachloride (CCl₄) activity is defined herein as the ratio (in percent) of the weight of CCl₄ adsorbed by an activated carbon sample to the weight of the sample, when the carbon is saturated with CCl₄ under conditions listed in this test method.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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. Specific hazards statements are given in Section 7.