21 CFR § 182.1711 - Silica aerogel.

(a) Product. Silica aerogel as a finely powdered microcellular silica foam having a minimum silica content of 89.5 percent.

(b) [Reserved]

(c) Limitations, restrictions, or explanation. This substance is generally recognized as safe when used as a component of an anti-foaming agent in accordance with good manufacturing practice.