U.S. Code of Federal Regulations
Regulations most recently checked for updates: Aug 28, 2025
(a) Alkalinity. Strongly alkaline to litmus.
(b) Ammonia content. 27 to 30 percent by weight. Accurately weigh a glass-stoppered flask containing 25 mL of water, add about 2 mL of the sample, stopper, and weigh again. Add methyl red indicator, and titrate with 1 N sulfuric acid. Each mL of 1 N sulfuric acid is equivalent to 17.03 mg of NH
(c) Color. Colorless liquid.
(d) Non-volatile residue. 2 mg maximum. Dilute a portion of the sample with 1
(e) Odor. Characteristic (exceedingly pungent).
(f) Specific gravity at 20 °/4 °C. 0.8920 to 0.9010.