Cal. Health & Safety Code § 108660

For bags of charcoal, the warning label specified in Section 108655 shall appear within a heavy borderline in a color sharply contrasting to that of the background, on both front and back panels in the upper 25 percent of the panels of the bag at least two inches below the seam, and at least one inch above any reading material or design elements in type size as follows: The signal word “WARNING” shall appear in capital letters at least three-eighths inch in height; the remaining text of the warning shall be printed in letters at least three-sixteenths inch in height.