Part 4 of this document, in addition to Part 1, specifies requirements for flat and long products of hot rolled weldable fine grain structural steels in the thermomechanical rolled condition in the grades and qualities given in Tables 2 to 4 (chemical composition) and Tables 5 to 7 (mechanical properties) in thickness £ 120 mm for flat products and in thickness £ 150 mm for long products. In addition to EN 10025-1 the steels specified in this document are especially intended for use in heavily loaded parts of welded structures such as, bridges, flood gates, storage tanks, water supply tanks, etc., for service at ambient and low temperatures.