ansi 9standards0 code issues - 31.3 and 31254 material

huangyhg

ansi 31.3 and 31254 material
is it permitted to construct pressure piping (31.3 piping) using 31254 material, when 31.3 does not give allowable stress?
can we us asme sec ii d allowable stresses (it is observed that for all the other material, values of  asme sec ii d is equal or conservaive as compared to ansi  b 31.3) to design and  construct 31.3 piping work?

according b31. 3 you are allowed to use unlisted materials if they are conform a published specification. allowable stresses shall be determined in accordance with b31.3 par. 302.3.2 or more conservative.