Table 2.

Minimum concrete cover depth (mm) for corrosion induced by carbonation.

Environmental Requirement for Minimum Concrete Cover Depth (mm)	Structural Class
Exposure Class: Corrosion Induced by Carbonation	S1	S2	S3	S4	S5	S6
XC1—Dry or permanently wet	10	10	10	15	20	25
XC2—Wet, rarely dry	10	15	20	25	30	35
XC3—Moderate humidity	10	15	20	25	30	35
XC4—Cyclic wet and dry	15	20	25	30	35	40