High tech and safe chemical reactions create the effects. Unlike traditional gunpowder with pyrotechnics, which has a much shorter blast of 10 seconds, indoor fireworks can last for minutes at a time. The duration, height and timings of the blasts can also be varied to create the special effects you require, and even timed to different sequences according to your event requirements. Even more, these fireworks are so safe that you can run your hand through them!
Take a look at the video demonstration below to see exactly how these work.