(a) Surf clams less than four inches in the longest diameter may not be taken from certified waters. When unintentionally and unavoidably taken, surf clams of less than four inches in the longest diameter may comprise, by number, no more than 20 percent of any catch.

(b) For the purpose of determining compliance with this section, not less than one representative U.S. standard bushel may be taken from a container or from any lot for examination. If the amount taken for examination is found to contain a number of surf clams of less than four inches in the longest diameter in excess of 20 percent by count, the container or lot from which such sample was taken is be deemed to contain in excess of 20 percent of surf clams of less than four inches in the longest diameter.

(c) If the procedure specified in subdivision (b) of this section establishes that more than 10 percent of containers which comprise a vessel's total catch contain in excess of 20 percent of surf clams of less than four inches in the longest diameter, all containers comprising such total catch are deemed to contain in excess of 20 percent of surf clams less than four inches in the longest diameter.