AbstractVDI (Society of German Engineers) submitted a new version for pressure release of dust explosions in November 1992 which will replace the June 1979 edition. Equations are now favored and nomograph take second place. NFPA 68, 1988 edition, which was reissued in 1994 and is presently being revised already contained some newer data but used the same range of application as the 1979 VDI. Such range of application was now expanded from 1 m3down to 0.1 m3and from 1,000 m3to 10,000 m3. Static activation pressure was previously limited to 0.5 bar. Now 0.1 bar to 1 bar gage can be used. Dusts with a deflagration index of 800 bar·m/s can be dealt with. Previously the limit was set at 600 bar·m/s. It is the intent of this paper to show possible savings. Pressure and flame behavior outside vented vessels will be addressed as well as the special case for pneumatic conveyin