The proper sizing of microchannel dimensions and the management of internal features offer the possibility of inherently safe operation within the flammable limits of a combustible fluid stream while preserving the largest-possible flow dimensions for industrial-scale process capacity. Specifically, the microchanne! dimensions need not be restricted to gap distances below the quenching distance to be operated safely. Microchannel performance can be engineered to provide adequate heat transfer for flame propagation. However. it is essential to maintain flame characteristics in such a manner that it cannot transition to a detonation flame front. A detonation takes place when the combustion wave propagates at supersonic speeds at the existing local temperature and pressure conditions in the system. It results in a much larger energy release over a much smaller period of time as compared to a laminar flame or deflagration. the later of which is a combustion wave propagating at subsonic speed. Detonations can be potentially highly destructive and very hazardous and therefore should be avoided for most industrial applications.