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Dust Explosions: An Overview 25

and the combination of mixers and plastic dusts is favorable for generating electrostatic
discharges. Section 9.5 in Chapter 9 provides references to more recent German statistics.
Proust and Pineau (1989) showed that there is reasonably good agreement between the
findings of Beck and Jeske for the Federal Republic of Germany and statistics of indus-
trial dust explosionsin the United Kingdom from 1979to 1984,as reportedby Abbot (1988).

1.2.4
RECENT STATISTICS OF GRAIN DUST EXPLOSIONS
1P-d THE UNITED STATES

Schoeff (1989)presented some statisticaldata that are shown in a slightlyrearrangedform
in Table 1.8.The data for 1900-1956 are from the same source as the data in Table 1.3.
The alarming trend is that the annual number of explosions seems to increaserather than
decrease. The annual number of fatalities is also higher for the last period, 1979-1988,
than for the previous one, 1957-1975. The annual number of injuries for the last period
is higher than for both previous periods. From 1957-1975 to 1979-1988, the annual esti-
mated damage to facilities seems to have increased more than what can be accounted
for by inflation. Section9.5 in Chapter 9 provides references to more recent U.S. statistics.

Table 1.8 Grain dust explosions in the United States: recent development

Source: Data from Schoeff, 1989.
It can be misleading to take the figures in Table 1.8too far. However, the data do indi-
cate that dust explosions remain a persistent threat to human life and limb and to prop-
erty. Therefore, the efforts to fight the dust explosion hazard have to continue.

l"3
DUST AND DUST CLOUD PROPERTIESTHAT INFLUENCE
KNITABILITY AND EXPLOSIONVIOLENCE

1.3.1
DUST CHEMISTRY, INCLUDING MOISTURE

There are two aspects to consider, the thermodynamics of the explosion and the kinet-
ics. Thermodynamicsis concernedwith the amount of heat liberatedduring combustion;
kinetics with the rate at which the heat is liberated.