Dust Explosions - Substances, Critical Temperatures and Concentrations
Basic rules to observe for dust to be capable of causing a dust explosion:
- The dust must be combustible
- The dust must be airborne
- The dust must have a size distribution capable of flame propagation
- The dust concentration must be within the explosive concentration range
- An ignition source with high enough temperature must be present
- The atmosphere must contain sufficient oxygen to support and sustain combustion.
Critical temperatures and concentrations:
| Substance | Ignition Temperature of Dust Cloud (oC) | Minimum Explosive Concentration (oz/ft3) | Relative Explosion Hazard |
|---|---|---|---|
| Alfalfa | 460 | ||
| Aluminum | 650 | 0.045 | Severe |
| Al-Mg alloy | 0.02 | Severe | |
| Cereal grass | 550 | ||
| Chromium | 0.23 | Strong | |
| Coal | 610 | 0.055 | Strong |
| Copper | 900 | Fire | |
| Corn | 400 | ||
| Epoxy Resin | 530 | 0.020 | Severe |
| Flax shive | 430 | ||
| Grain dust, winter wheat, corn, oats | 430 | ||
| Iron | 420 | 0.100 | Strong |
| Magnesium | 520 | 0.020 | Severe |
| Rice | 440 | ||
| Silicon | 0.11 | Strong | |
| Soy flour | 540 | ||
| Tin | 630 | 0.190 | Moderate |
| Titanium | 460 | 0.045 | Severe |
| Uranium (finely divided metal dust) | 20 | 0.060 | Severe |
| Wheat flour | 380 | ||
| Wheat straw | 470 | ||
| Zinc | 600 | 0.480 | Moderate |
- missing data not available at the moment
- 1 ft3 = 0.02832 m3= 28.32 dm3 = 0.03704 yd3 = 6.229 Imp. gal (UK) = 7.481 gal (US) = 1,728 Cu.In.
- 1 oz (ounce) = 28.35 g = 437.5 grains = 0.0625 lb = 0.0000279 long ton (UK) = 0.00003125 long ton (US) = 0.000558 long hundredweight (UK) = 0.000625 long hundredweight (US) = 0.004464 stone = 16 dram
Related Topics
• Material Properties
Properties of gases, fluids and solids. Densities, specific heats, viscosities and more.
• Miscellaneous
Engineering related topics like Beaufort Wind Scale, CE-marking, drawing standards and more.
• Risk, Reliability and Safety
Risk, reliability and safety in process control systems.
• Temperature Measurements
Measurment of temperature - probes, sensors and transmitters.
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