① Type A may be furnished as a vacuum degassed, at the producer option.
② The sum of copper, nickel, chromium, and molybdenum shall not exceed 0.50 % on heat analysis. When one or more of these elements is specified, the sum does not apply; in which case, only the individual limits on the remaining elements will apply.
③ Chromium is permitted at the producer option, to 0.25 % maximum when the carbon is less than or equal to 0.05 %. In such case, the limit on the sum of the four elements in Footnote ② does not apply.
④ For carbon levels less than or equal to 0.02 %, columbium and/or titanium may be used as chemical stabilizing elements at the producer option. When such is the case, the limits above do not apply to those elements. Rather, the limit on columbium shall be 0.10% maximum and the limit on titanium shall be 0.15% maximum.
