K.L. and B.J Kosanke The time chosen for the interval between a shell firing and its burst is sometimes given less thought than it deserves. By carefully choosing the delay interval provided by the time fuse, it may be possible to produce undistorted bursts, with a higher level of safety. When an aerial shell bursts, …
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Month:March 2007
Fireball Characteristics as Determined in a Test Simulating the Early Stage of a Fireworks Truck Loading Accident
K.L. and B.J Kosanke A few years ago there was an investigation and analysis of an accident thought to have been initiated by the ignition of a case of spherical aerial shells in the cargo area of a truck. It was thought that the case of shells had been dropped or thrown to the floor …
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Pyrotechnic Burn Rate Measurements: Strand Testing
K.L. and B.J Kosanke Background: Burn rate is one of the most fundamentally important properties of pyrotechnic materials. While burn rate may be measured as a mass burn rate (mass of pyrotechnic composition consumed per unit time, e.g., g/s), linear burn rate is most commonly used. Linear burn rate can be defined as the distance …
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“Impossible” and Horrific Roman Candle Accident
K.L. and B.J Kosanke [Authors note: This article includes a number of notes with ancillary information. This information is not essential to the primary purpose of this article. Accordingly, it is suggested that the reader might wish to initially ignore the notes, and then subsequently, if additional information is desired, read any notes of interest.] …
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Aerial Shell Burst Delay Times
K.L. and B.J Kosanke If you have ever wondered how long the shell burst process takes after the time fuse burns through to the interior of the shell, this article may be of interest to you. Although rapid, the process is not instantaneous. A flame front must advance through the burst charge and an amount …
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Aerial Shell Burst Height as a Function of Mortar Length
K.L. and B.J Kosanke [This article is augmented with a number of text notes, indicated using superscript letters. While it is hoped these provide useful information, they are not essential, and the reader may wish to ignore them unless further information is desired.] From time to time over the years there has been discussion of …
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A Rule for Improving Manufacturing Safety
K.L. and B.J Kosanke Over the years there has been an almost continuous series of accidents involving people using energetic materials, too many of which involve fireworks, their manufacture or their preparation for use. There are important lessons that can be learned from these accidents; unfortunately most of these come too late for the people …
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DOT Exemption for Display Fireworks with Electric Matches Attached
K.L. and B.J Kosanke Background: Several years ago the US Department of Transportation granted an exemption[1] that, undercertain conditions, “authorizes the transportation in commerce of Division 1.3 and 1.4 display fireworks with igniters (electric matches) attached to either the fuse or the lift charge.” Because of concern regarding one of the specific provisions of that …
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Sodium/Potassium Ratio and Hygroscopicity of Civil War Era Black Powder
K.L. and B.J Kosanke Several years ago a sample of Black Powder, which had previously been recovered from US Civil War era cannon balls (ca. 1865), was made available for analysis. This made possible a brief comparative study of the Civil War era sample and one representing currently produced Black Powder. That study found the …
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Studies of Electric Match Sensitiveness
K.L. and B.J Kosanke ABSTRACT: The sensitiveness of a collection of ten electric match types, from four suppliers, was determined under conditions intended to reflect their actual use to ignite fireworks displays. The measurements included determinations of impact, electrostatic discharge (ESD), friction, and thermal sensitiveness. The ESD tests considered discharges both through the bridgewire and …
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