1.1 This specification covers lightweight aggregates intended for use in concrete not exposed to the weather, in which the prime consideration is the thermal insulating property of the resulting concrete. 1.2 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard. 1.3 With regard to sieve size and the size of aggregate as determined by the use of testing sieves, the values in inchpound units are shown for the convenience of the user; however, the standard sieve designation shown in parentheses is the standard value as stated in Specification E11. 1.3.1 With regard to other units of measure, the values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.4 The following precautionary caveat pertains only to the test method portion, Section 6, of the specification: 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.