“…Results of check of hypotheses by Pearson , s criterion (significance value α =0,05, number of degrees of freedom 3 shows the numerical values of the actual and normative values of the coefficients of variation and also the maximum possible allowed value (AQD) for some the protective -decorative coverings. Analysis of the data shows that some of coverings are characterized by lower uniformity values of the bond strength, than it is required, proceeding from a ratio of actual and normative coefficients of a variation [16,17,18,19,20]. The maximum allowed value the average-quadratic deviation at statistical controllability of process of painting for some coverings (PVAC, polymerlime, PF-115) must be less than the actual and must correspond to the values from table 3.…”