ASTM C207-18 PDF Download

ASTM C207-18 is a standard specification that covers four types of hydrated lime for masonry purposes. The specification defines Type N and Type S hydrated lime, which are suitable for use in various applications such as mortar, cement plaster, stucco, and addition to Portland-cement concrete. It also defines Type NA and Type SA hydrated lime, which are air-entrained and have the same applications as Type N and Type S, but with the added benefit of air-entrainment.

The specification outlines the required chemical composition for calcium and magnesium oxides and carbon dioxide in the hydrated lime. It specifies that the hydrated lime covered by Types N or S should not contain any additives for the purpose of entraining air. Additionally, the specification provides distinctions between special hydrated lime (Type S) and special air-entraining hydrated lime (Type SA) compared to normal hydrated lime (Type N) and normal air-entraining hydrated lime (Type NA). These distinctions include properties like plasticity, water retentivity, and limitations on unhydrated oxide content.

Furthermore, the specification includes informative notes that address important considerations. These notes highlight that the use of air-entraining materials in mortar may be restricted by some building codes due to potential reductions in bond and compressive strength. However, air-entraining lime can provide increased freeze-thaw resistance when necessary. The specification also mentions that lime putty should be referenced separately in Specification C1489, and that specifications for normal and special finishing hydrated lime can be found in Specification C206.