①Elements not quoted shall not be intentionally added to the steel without the agreement of the purchaser except for finishing the cast. All reasonable precautions are to be taken to avoid the addition of such elements from scrap and other materials used in manufacture which affect the mechanical properties and the suitability. However, if agreed, the manufacturer can add elements such as Ca, Se,Te, etc. for the purpose of improving the machinability. These elements have to be reported in the inspection document.