Spot Radiography. Except when spot radiography is required for Category B or C butt welds by (a)(5)(b) above, butt welded joints made in accordance with Type No. (1) or (2) of Table UW-12 which are not required to be fully radiographed by (a) above, may be examined by spot radiography. Spot radiography shall be in accordance with UW-52. If spot radiography is specified for the entire vessel, radiographic examination is not required of Cate-gory B and C butt welds in nozzles and communicating chambers that exceed neither NPS 10 (DN 250) nor 11⁄8 in. (29 mm) wall thickness.