MIL-STD-1894 Radiographic Reference Standards And Radiographic Procedures For Partial-Penetration Steel WeldsThis standard provides standard reference radiographs and recommended radiographic inspection procedures for partial-penetration weldments in steel plate, casting, or forging, 0.5 to 2 inches \(in.\) \(12.70 to 50.80 millimeters \(mm\)\) thick.