Section 173.431 - Activity limits for Type A and Type B packages(a) Except for LSA material and SCO, a Type A package may not contain a quantity of Class 7 (radioactive) materials greater than A1 for special form Class 7 (radioactive) material or A2 for normal form Class 7 (radioactive) material as listed in §173.435, or, for Class 7 (radioactive) materials not listed in §173.435, as determined in accordance with §173.433.(b) The limits on activity contained in a Type B(U) or Type B(M) package are those prescribed in §§173.416 and 173.417 , or in the applicable approval certificate under §§173.471, 173.472 or 173.473.Amdt. 173-244, 60 FR 50307, 9/28/1995, as amended at 69 FR 3677, 1/26/2004