ACI 318 "Building Code Requirements for Reinforced Concrete" is one of the most influential standards of the American Concrete Institute because it is widely adopted by local governments as part of their building codes. Thus it takes on the force of law in many areas.

CHLORIDE RESTRICTIONS IMPLEMENTED

In Chapter 4, Concrete Quality, the proposed new Section 4.5.3.1 states "Calcium chloride as an admixture shall not be used in concrete to be exposed to severe or very severe sulfate containing solutions, as defined in Table 4.5.3." Examination of the referenced table shows that these exposure conditions include all soils with a water-soluble sulfate (SO4) content more than 0.20 percent by weight and all water with a sulfate content more than 1500 parts per million.

Section 4.5.4 of the proposed 318 revision states further: "For corrosion protection, maximum water soluble chloride ion concentrations in hardened concrete at an age of 28 days contributed from the ingredients including water, aggregates, cementitious materials and admixtures shall not exceed limits of Table 4.5.4.