American Concrete Institute (ACI). ACI 523.3R-93. 2014. 17 p. This guide applies to cellular concretes with cast densities greater than 50 lb/ft3 (800 kg/m3). Precast and cast-inplace cellular concretes are within the scope of this guide. Compressive strengths may vary widely and are specified based on a particular application. To assist in selection, proportioning, and production of cellular concretes, the available material property information and applications of cellular concretes are also addressed.