What regulations control the use of hybrids?
NOX is a compressed gas, and is subject to any regulations that might apply to the handling of compressed gases. The commercial hybrid motors use fuel grains that are non-hazardous, usually some form of plastic. Some hybrids use a small amount of conventional solid rocket propellant as an igniter or preheater. As long as this igniter grain is under 62.5 grams, it is only subject to the same regulations as a composite model rocket motor.
