In the area of concrete construction, where much depends on know how, patience and careful workmanship, it was only natural that short cuts should be offered in the form of admixtures. Of all the many products put on the market in the last few decades, one has risen head and shoulders above the others in its effectiveness. It is the air entraining agent. The introduction of air into concrete mixes has some pronounced effects on the characteristics of both the plastic and the hardened concrete. In fresh concrete, the tiny air bubbles act as a lubrication element in the mix which improves its workability and increases its slump. Air also produces "stickier" more cohesive concrete and as a result less segregation is experienced and more attractive surfaces are achieved. In hardened concrete, the outstanding attributes of air entrainment are the enhanced weatherability and resistance to scaling afforded. Air can be entrained in concrete by two methods: air entraining cements or air entraining agents. Air entraining materials included such products as natural wood resins, animal fats, wetting agents and water soluble soaps of certain acids. The material when combined with the other concrete constituents acts as a foaming agent. By lowering the surface tension of the waster a stable foam is generated which results in the formation of microscopic air voids.