1.1 This specification2 covers seamless ferritic and austenitic steel boiler, superheater, and heat-exchanger tubes, designated Grades T5, TP304, etc. These steels are listed in Tables 1 and 2. (A) Maximum, unless range or minimum is indicated. Where ellipses (...) appear in this table, there is no requirement, and analysis for the element need not be determined or reported.(B) It is permissible to order T2 and T12 with a sulfur content of 0.045 max. See 16.3.(C) Alternatively, in lieu of this ratio minimum, the material shall have a minimum hardness of 275 HV in the hardened condition, defined as after austenitizing and cooling to room temperature but prior to tempering. Hardness testing shall be performed at mid-thickness of the product. Hardness test frequency shall be two samples of product per heat treatment lot and the hardness testing results shall be reported on the material test report.(D) Applies to both heat and product analyses.(E) The terms Niobium (Nb) and Columbium (Cb) are alternate names for the same element. (A) Maximum, unless a range or minimum is indicated. Where ellipses (...) appear in this table, there is no minimum and analysis for the element need not be determined or reported.(B) The method of analysis for Nitrogen shall be a matter of agreement between the purchaser and the producer.(C) For these alloys, there is no common grade designation. The UNS number uniquely identifies these alloys.(D) For small diameter or thin walls, or both, where many drawing passes are required, a carbon maximum of 0.040 % is necessary in Grades TP304L, TP304LN, TP316L, and TP316LN.(E) Grade S30434 shall have (Ti + 1/2 Nb) of not less than 2 times and not more than 4 times the carbon content.(F) Grade TP347LN shall have an Nb content of not less than 15 times the carbon content.(G) Grade TP348 shall have an Nb + Ta content of not less than 10 times the carb