Three gallons of ammonia, aqueous, 27 to 30 percent by weight; 3 gallons of strong ammonia solution, N.F.: 17.5 pounds of caustic soda, liquid grade, containing 50 percent sodium hydroxide by weight; or 8.75 pounds of potassium hydroxide, on an anhydrous basis; 12.0 pounds of caustic soda, liquid grade, containing 73 percent sodium hydroxide by weight.
27 C.F.R. § 21.63