An active clearance is one in which the candidate is presently eligible for access to classified information. A current clearance is one in which a candidate has been determined eligible for access to classified information but is not currently eligible without a reinstatement.
The NCTM Standards evolved over several years, beginning with the 1980 report An Agenda for Action (NCTM, 1980), an important precursor to the NCTM Standards documents. A set of events and circumstances took place in the 1980s that spurred the need for standards and for national direction in mathematics education.
ASTM. ASTM stands for American Society for Testing and Materials. The organization develops over 12,500 voluntary consensus standards. They have over 140 technical standards-writing committees and represent many diverse industries. The committees include producers and users and consumers who have general interest in the products. The following standards are the most important and deal with playgrounds. There are also many others.