Maximum Span Tables BS4592 part 1, states three categories of load: i) 3 kN/m2 - Light Duty, access limited to one person. ii) 5 kN/m2 - General Duty, regular pedestrian traffic. iii) 7.5 kN/m2 - Heavy Duty, high density pedestrian traffic. The values have been calculated with deflections limited to 1/200th of the span or 10mm whichever is the lesser. Some sections and types are subject to a minimum order quantity. If you have any further questions, please contact our sales team for assistance. These values on each of the following tables are in mm and represent the maximun unsupported span of gratings to achieve load shown. 15mm Pitch   Load UDL Load Bar 3kN/m2 5kN/m2 7.5kN/m2   Clear Span (mm) 40x3 2765 2434 2199 30x3 2229 1949 1703 30x2 2014 1703 1487 25x3 1926 1624 1419 25x2 1682 1419 1239 20x3 1826 1540 1346 20x2 1540 1299 1135 21mm Pitch   Load UDL Load Bar 3kN/m2 5kN/m2 7.5kN/m2   Clear Span (mm) 40x3 2548 2242 2026 30x3 2053 1747 1526 30x2 1810 1526 1333 25x3 1726 1456 1272 25x2 1508 1272 1111 25mm Pitch   Load UDL Load Bar 3kN/m2 5kN/m2 7.5kN/m2   Clear Span (mm) 70x4 3753 3303 2985 60x4 3516 3094 2796 50x4 3273 2881 2603 40x4 2769 2437 2202 40x3 2437 2145 1918 30x3 1952 1646 1438 30x2 1705 1438 1256 25x3 1627 1372 1199 25x2 1421 1199 1047 30mm Pitch   Load UDL Load Bar 3kN/m2 5kN/m2 7.5kN/m2   Clear Span (mm) 60x5 3581 3152 2848 50x5 3124 2749 2484 40x5 2642 2325 2101 40x3 2325 2047 1802 35x5 2390 2104 1869 35x3 2104 1805 1577 30x5 2129 1834 1602 30x3 1834 1547 1351 25x5 1812 1528 1335 25x3 1528 1289 1126 20x3 1223 1031 901 34mm Pitch   Load UDL Load Bar 3kN/m2 5kN/m2 7.5kN/m2   Clear Span (mm) 60x5 3471 3055 2760 50x5 3027 2664 2408 40x5 2561 2254 2037 40x3 2254 1978 1728 35x5 2317 2039 1793 35x3 2039 1731 1512 30x5 2064 1759 1537 30x3 1759 1484 1296 25x5 1738 1466 1281 25x3 1466 1236 1080 20x3 1173 989 864 41mm Pitch   Load UDL Load Bar 3kN/m2 5kN/m2 7.5kN/m2   Clear Span (mm) 60x5 3316 2919 2637 50x5 2893 2546 2300 40x5 2447 2153 1928 40x3 2153 1862 1626 35x5 2214 1931 1687 35x3 1931 1629 1423 30x5 1963 1655 1446 30x3 1655 1396 1220 25x5 1636 1379 1205 25x3 1379 1163 1016 20x3 1104 931 813 back to products