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Why doesn't F710 address these items more thoroughly? Because the standards were advanced by flooring industry representatives. These standards are not based on the specified properties of concrete or the proportions of its various ingredients. Nor do they defer to project plans or specifications. Yet the flooring industry has produced over-reaching and ambiguous standards for which they hold the members of the concrete industry accountable. The result is expensive litigation, leading to failures and bankruptcies of some concrete-related businesses.

The F710 standard and its Appendixes suggest what to expect for water-cement ratio (w/cm) and the pH of concrete: as the w/cm ratio increases "most concrete properties are affected negatively." An increased pH is also considered to have a negative effect. But these expectations are unsupported by any references - and they are contradictory.

Fresh concrete has a pH of 12 or higher, and a low w/cm ratio maintains that high pH. But, according to the flooring standard, concrete slabs with high pH values should be excluded from receiving resilient flooring because high alkalinity damages flooring materials. Yet higher w/cm ratios usually reduce the cured surface pH to what the standard suggests are preferred levels.

The writers of the standard seem to want the concrete both ways: low w/cm for low permeability and higher w/cm to reduce the pH to levels they prefer. Unfortunately, these properties are mutually exclusive.

There is little uniformity or standardization in the way pH testing of concrete surfaces is performed. This test can provide misleading results because test solutions change over time and test methodologies vary greatly. Thus, these tests are inconsistent and unreliable, much like vapor emission tests.