Evaporation Retarder: Apply a waterborne monomolecular evaporation retarder to concrete surfaces, as recommended by ACI 305R, ACI 308, and ACI 345R if hot, dry, or windy weather conditions cause moisture loss approaching 0.1 lb/sf/hr as determined using the Menzel Evaporation Rate chart. Apply according to manufacturer's written instructions after placing, screeding, and bull floating or darbying concrete, but before final finishing operations. Evaporation rate calculations will be confirmed by the engineer. Failure to use an evaporation retarder will be grounds for rejection of the concrete. The engineer shall approve all evaporation retarding materials. Evaporation retarders are not required where water fogging equipment is in use.
