Sensitivity to Spark

In addition, H2 is extremely sensitive to spark initiation, and can cause premature detons when ammo is being handled, is in-tube during launch, or is being steam-cleaned for reloading, purposes. A parallel reaction involves the release of NH3, which can combine with metals such as Cu in the presence of nitrates to form such extremely shock sensitive compds as tetramino cupric nitrate (Ref 17). To obviate these effects, desiccants such as silica gel may be added to the extent of 0.5% (Ref 12)... 

Finely powdered silicon can give significant dust explosion hazards. Relationships of sensitivity to spark ignition and of explosibility to particle size are studied [1]. Maximum explosion pressures of 6.4 bar, with maximum rate of rise of 884 bar/s have been determined [2], Silicon dust is likely to result from processes using silanes in the gas phase [3],... 

Black powder is the oldest explosive in history, dating back to the eighth century. Its chemical composition is well-known as a mixture of potassium nitrate, sulfur, and charcoal. The mixture ratio is varied according to the purpose for which it is to be used, with the ranges kno3(0-58-0.79), (0.08-0.20), and ( (0.10-0.20). Black powder composed of particles less than 0.1 mm in diameter is used for shell burst of fireworks and fuses. The grade with diameter 0.4—1.2 mm is used for the launch of spherical shells of fireworks, while that with diameter 3-7 mm is used in stone mines. Since black powder is sensitive to sparks caused by mechanical impact, friction, and static electricity, black powder containers should be made of brass or aluminum alloys rather than iron or steel. When Cl and Ca or Mg are present as impurities, CaClj or MgClj is formed and the thermal performance of KN is reduced. Contamination with NaCl also needs to be avoided for the same reason. 

Fireworks, when not properly handled, can result in injury, loss of life and property damage. The problems of safety are in many ways different from those of most explosives and propellants. In general, the sensitivity of fireworks to shock and impact is considerably less than that of many explosives and propellants. On the other hand, most fireworks are more sensitive to sparks and flame than most other explosive materials. 

The standard American flash and sound composition is a blend of potassium perchlorate, sulfur or antimony sulfide, and aluminum. The ignition temperature of this formulation is several hundred degrees higher than chlorate-based mixtures, but these are still very dangerous compositions because of their extreme sensitivity to spark and flame. Ignition of a small portion of a "flash and sound" mixture will rapidly propagate through the entire sample. These mixtures should only be prepared remotely, by experienced personnel. Table 8.5 hsts several "flash and sound" formulas. 

DOT CLASSIFICATION Forbidden SAFETY PROFILE Moderately toxic by inhalation. Experimental reproductive effects. Mutation data reported. An eye irritant. A powerful explosive sensitive to spark, impact, sunlight, or heating rapidly to 100°C. A powerful oxidizer. Concentrations of greater than 10% in air are explosive. Explodes on mbting with carbon monoxide, hydrocarbons (e.g., butadiene, ethane. 

Human poison by ingestion. Experimental poison by ingestion, intraperitoneal, and intravenous routes. Human systemic effects by skin contact cyanosis and motor activity changes. Experimental reproductive effects. An eye irritant. Mutation data reported. Mixture with nitric acid is a high explosive. Mixture with tetranitromethane is a high explosive very sensitive to sparks. When heated to decomposition it emits toxic fumes of NOx. See also o- and p-DINITROBENZENE. 

Bottle can be u ed wet or after olution has dried. How ever, when dry, the sugar - Potassium chlorate mixture is very sensitive to spark or flame and should be handled accordingly. 

In summary, zirconium-oxidizer mixtures will be very sensitive to spark, and they will react very quickly to produce high-temperature sparks ideal for ignition compositions. When you need to light something very quickly with high reliability, these might be materials you would choose. Otherwise, the sensitivity hazards of zirconium preclude wider use of the material. 

---