February 18th, 2009

  • roybot

Dangerous instructions.

"Certain formulations, notably aluminium powder and potassium chlorate with or without sulfur, become less stable over time and may combust with little or no warning. Modern pyrotechnic practices call for never using sulfur in a mix containing chlorates. that produces a loud and sometimes powerful explosion. The key point is that flash powder can explode without being contained. Just about any amount of flash powder will explode if contained, but it can also explode without being contained if the pile Small quantities (less than a tablespoon) of non-contained flash powder usually burn without making a report (audible explosion) unless the quantity is above its hypercritical mass. A loose pile (tablespoon) of flash powder can "explode" or cause a loud report without being contained in a tube or another type of container, which can lead to injury or damage if this outputpowerful explosion. The key point is that flash powder can explode without being contained. Just about any amount of flash powder will explode if contained, but it can also explode without being contained if the pile is large enough. The point at which open flash powder explodes will vary by formula (i.e. amount of sulfur, aluminum quality, etc.), so be aware that flash is not expected or desired. Example: a small quantity of flash powder is placed on an open surface (ground) and ignited. The output is a brilliant white flash and smoke, but relatively no noise. Next a larger amount of flash powder is similarly situated and ignited. Assuming the amount of flash powder is large enough to allow its own mass due to gravity to contain itself, the reaction will result in a deflagration, similar to a detonation is large enough. The point at which open flash powder explodes will vary by formula (i.e. amount of sulfur, aluminum quality, etc.), so be aware that flash powder will explode without being contained if the amount is large enough. Measurements are approximate and illustrative."

Posted by wolf530 (analog hacker extraordinaire)