Determines aspects of manufacture, and the inspection and repair welding procedures for ferritic steel valve body and bonnet castings. It does not cover the requirements for discs or other internal fittings. The valve castings have been categorised into six inspection levels. Guidance is given in Appendix A on the choice of levels. Unless otherwise stated in this Standard, all castings shall meet the requirements of BS 1504. Does not apply to turbine steam chests.