This test method covers determination of compressive strength of cylindrical concrete specimens such as molded cylinders and drilled cores. It is limited to concrete having a unit weight in excess of 800 kg/m3 (50 lb/ft3). The values stated in SI units are the preferred standard. This standard may involve hazardous materials@ operations@ and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Warning?? Means should be provided to contain concrete fragments during sudden rupture of specimens. Tendency for sudden rupture increases with increasing concrete strength (Note 1). Note 1??The safety precautions given in the Manual of Aggregate and Concrete Testing@ located in the Related Materials section of Volume 04.02 of the Annual Book of ASTM Standards@ are recommended. The text of this standard references notes which provide explanatory material. These notes shall not be considered as requirements of the standard.