Investigation on the flammability limits of some refrigerant mixtures with flammable components.

An experimental apparatus has been built to measure the flammability limits of combustible gases based on Chinese national standard GB/T 12474-90. The flammability limits of four binary mixtures of R161/R134a, R152a/R134a, R161/N2 and R152a/N2 were measured with this apparatus at atmospheric pressure and ambient temperature. Comparisons were made with the literature data; good agreement for most measurements was obtained. R134a was found to have a better dilution effect than nitrogen in reducing the flammability of hydrofluorocarbons.