Rule 18
Primary source
Verbatim text below is from the Electronic Code of Federal Regulations (eCFR), a public-domain U.S. government work. Always verify the current version with the eCFR before relying on it for any legal matter.
Full Text
Burn shall be determined as the average burning time of leaves selected at random from the sample. A minimum of 10 leaves shall be selected as representative regardless of the number of bundles or bales in the lot. All burn tests shall be made in the bindercutting area on the same side of the leaf. The leaf shall be punctured to permit quick ignition when placed over a candle, alcohol lamp, or electrical-lighting device. Good burn shall average 6 seconds or longer; fair burn, 3 to 5 seconds; and poor burn, under 3 seconds. B1 and B2 shall require good burn and B3, fair burn.
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