How BIG?

"How big is that explosion going to be?" That's a question the Pyro's get when organizing a professional firework display.

First lets look at what happens when a firework is ignited:

Inside a fireworks shell are several components: 1) the lift charge, 2) the delay fuse, 3) the burst charge 4) the stars (and effects).

Once a shell fuse is ignited the lift charge ignites the delay fuse and pushes the shell out of the mortar tube. As the shell climbs into the sky the delay fuse slowly burns away.
When the shell reaches the apex (the height at which the shell will begin to arc over and let gravity take it back to Earth.) the delay fuse will reach the burst charge and set it off!
The high heat of the burst charge ignites the stars while the pressure forces the shell to break open and flings the stars into the night sky!


So how BIG is B I G? Well simply put...

Stars dispersion is, according to the Explosives Regulator Division of Natural Resources Canada, "The maximum distance that stars (pyrotechnic effects) are projected by the explosion of the burst charge is approximately 27 m in diameter for 25 mm of the nominal shell diameter."

Don't worry about trying to calculate that as we've made it easy for you. Refer to our diagram, share with friends, print it out and bring it to your next big professional display!

Have a blast!