Dust Explosibility Properties - P_MAX and K_ST

A very serious risk in dust processing environments is the ignition of a dust cloud
within an enclosed volume. If not relieved or suppressed, the developing deflagration
will result in a rapid rise in pressure and an ensuing explosion. The design of
explosion protection measures requires an understanding of the deflagration
characteristics of dust clouds. ASTM E1226 Standard Test Method for Pressure
and Rate of Pressure Rise for Combustible Dusts is used to determine maximum
deflagration pressure, P_MAX, rate of pressure rise, (dP/dt)_MAX, and K_ST. This type of
testing is also called “dust explosion testing.” The data obtained from this test is
useful in the design of explosion protection systems such as pressure relief vents
(per NFPA 68) and suppression systems. 

Tests are conducted on fine dry dusts. Test standards recommend that the test be
conducted on fine dusts, i.e., dust passing through a No. 200 sieve screen (or a
No. 230 sieve screen when testing in accordance to EN requirements). If the moisture
content is more than 5% then the sample is dried.

Sample size:  1000 g