1. Percentages of alcohol, such as those under the heading Alcohol content, refer to percentage by volume of C2H5OH at 15.56 . 2. Where a formula, test, or assay calls for alcohol, ethyl alcohol, or ethanol, the USP monograph article Alcohol shall be used. 3. Where reference is made to “C2H5OH,” absolute (100 percent) ethanol is intended. 4. Where a procedure calls for dehydrated alcohol, alcohol absolute, or anhydrous alcohol, the USP monograph article Dehydrated Alcohol shall be used.