Section 184.1545 - Nitrous oxide(a) Nitrous oxide (empirical formula N2O, CAS Reg. No. 10024-97-2) is also known as dinitrogen monoxide or laughing gas. It is a colorless gas, about 50 percent heavier than air, with a slightly sweet smell. It does not burn but will support combustion. Nitrous oxide is manufactured by the thermal decomposition of ammonium nitrate. Higher oxides of nitrogen are removed by passing the dry gas through a series of scrubbing towers.(b) The ingredient must be of a purity suitable for its intended use.(c) In accordance with § 184.1(b)(1) , the ingredient is used in food with no limitations other than current good manufacturing practice. The affirmation of this ingredient as generally recognized as safe (GRAS) as a direct human food ingredient is based upon the following current good manufacturing practice conditions of use: (1) The ingredient is used as a propellant, aerating agent, and gas as defined in § 170.3(o)(25) of this chapter.(2) The ingredient is used in dairy product analogs as defined in § 170.3(n)(10) of this chapter at levels not to exceed current good manufacturing practice.(d) Prior sanctions for this ingredient different from the uses established in this section do not exist or have been waived.48 FR 57270, Dec. 29, 1983, as amended at 73 FR 8607 , Feb. 14, 2008