... , ANSI/NAAMM-MBG531, BS4592, AS1657, JS31011.3 Grating Dimension Load Bearing Flat Bar sizeThickness≥3mm, depth ≥ ... 25X4.7, 25X5…..40X6, 40X8, 40X10,….90X6….Pitch of Load bearding flat bars(mm)12.5,15, 20, ... 34.8, 35.3, 40, 60, 80……Pitch of cross bars(mm)38.1, 50, 50.8, 70 ... . Galvanized, b. Untreated (black self-color), c. Painted 2. design can be customized according to site requirement. steel grating