Manufacturing Fireworks: The Processes Involved

With 4^th of July celebrations coming up this weekend, we thought it might be nice to celebrate fireworks manufacturers. While this is a type of manufacturing that occurs outside of the machine shops in our nation, the process can be interesting to those who like to know and understand things. Though there is some mechanization involved in making the stars (the colored part of the explosion), the majority of the process typically requires little to no machining and is, instead left to master pyro-technicians who complete the job by hand.

While the earliest fireworks were paper or bamboo tubes stuffed with charcoal and sulfur, these early fireworks did not produce an explosion (just a flicker of lights and smoke). Many changes have come about since then, with more advanced fireworks being used in the United States since the nation’s early days. Scientific advances in the 20^th century, however, created increased dangers for celebrants, and both our federal and state governments began regulating fireworks as early as the 1930s.

There are multiple types of fireworks ranging from simple Oriental-style shells that produce spherical burst patterns to the more complex Italian-style shells that are responsible for the elaborate fireworks seen during a show.

Please note: this article is not meant to be a “how to” article and, as such, we have left out many of the finer details to discourage those who seek to create anything illegal. We advocate safe and legal celebrations for the 4^th of July.

The whole process begins with the creation of gunpowder which is shipped to fireworks manufacturers throughout the country. Once received, it is combined with a coloring agent and an oxidizer. Coloring agents and other effects can include a wide variety of different metals, but the most common are the following:

Once the coloring agent is added, the powdered mixture is sifted through spark-resistant screens, added to a tumbler, mixed with water, and formed into dough. This dough is then cut into different shapes and sizes to form pyrotechnic stars. The shape and size of the stars has a large effect on the fireworks seen in the air on the 4^th of July. That said, the patterns these stars are aligned in within the shell also makes a big difference in the patterns viewed in the night sky.

The shells of most fireworks are made of cardboard and generally come in two halves (of a globe). Once made, the stars are placed into the cardboard shells along with a breaking powder and a fuse. The halves are then put together, taped, wrapped repeatedly in paper and left to dry.

After the shell has dried, an additional fuse is attached to the outside along with a lift charge (to propel the firework upward). At this point, the fireworks are labeled, packaged and shipped to different locations across the country.

Like many other processes in manufacturing, this process is delicate, and precision is a necessity.  In light of this, Brooks Associates would like to tip our hats to those involved in manufacturing our Independence Day celebration fireworks for their hard work and meticulous efforts!