A cement accelerator is an admixture for the use in concrete, mortar, rendering or screeds. The addition of an accelerator speeds the setting time and thus cure time starts earlier. This allows concrete to be placed in winter with reduced risk of frost damage. Concrete is damaged if it does not reach a strength of 500 pounds per square inch (3.4 MPa) before freezing. 19 Our setting accelerators allow you to speed up the development of early strength values in your concrete.