Pyrotechnics - Proximate Pyrotechnics

Proximate Pyrotechnics

Explosions, flashes, smoke, flames, fireworks or other pyrotechnic driven effects used in the entertainment industry are referred to as theatrical special effects, special effects, or proximate pyrotechnics. Proximate refers to the pyrotechnic device's location relative to an audience. In the majority of jurisdictions, special training and licensing must be obtained from local authorities to legally prepare and use proximate pyrotechnics.

Many musical groups use pyrotechnics to enhance their live shows. Some of the earliest bands to use pyrotechnics were The Who, Pink Floyd, KISS and Queen, even Michael Jackson attempted using pyrotechnics in a 1984 Pepsi advertisement, where a stray spark caused a small fire in his hair. German industrial metal band Rammstein are renowned for their large variety of pyrotechnics, which range from flaming costumes to face-mounted flamethrowers. Nightwish, Lordi and Green Day are also known for their vivid pyrotechnics in concert. Many professional wrestlers have also used pyrotechnics as part of their entrances to the ring.

Modern pyrotechnics are, in general, divided into categories based upon the type of effect produced or manufacturing method. The most common categories are:

• Airburst - Hanging charges designed to burst into spheres of sparks.
• Binary powders - Kits divided into separate oxidizer and fuel, intended to be mixed on site.
• Comet (meteor) - Brightly colored burning pellets resembling shooting stars.
• Mine - Tubes containing a lift charge intended to project stars, sparks, confetti or streamers.
• Preloaded Smoke Pot - Cartridges designed to release a mushroom cloud of smoke.
• Concussion (cannon simulator,concussion tube) - Device designed to create a loud report.
• Falls - Propellant with titanium burning in an open ended tube creating a falling spark effect.
• Fireballs / Mortar Hits - Short barreled device projecting smoky rolling ball of flame.
• Flame Projector - Tube containing nitrocellulose granules that burn in pillars of colored flame.
• Flare (Torch) - Short, high intensity flames or various colours.
• Flash Cotton (Sparkle String) - Nitrated cotton string(nitrocellulose).
• Flashpaper - Sheets of nitrated paper (nitrocellulose) resembling tissue paper.
• Flash Pot - Short metal pot used with binary powders creating flash, smoke or sparks.
• Flash Tray (split mine) - A long tube slit down one side to project a sheet of flash.
• Gerb (including fountain, whistle, and waterfall) - A fountain of sparks.
• Lance - Small colored flare tube used in making points of light lancework or pictures in fire.
• Line Rockets - Whistling or colored rocket devices that travel along guide cables.
• Multi-Tube Article (multi-shot plate, multiple shot repeater boards and bombardo boards; designed to function in sequence) - Multiple effects chained together.
• Pre-Mixed Powder - Powders intended to create various effects. (Concussions, flashes, etc.)
• Squib - A small electrically initiated device replicating bullet hits.
• Strobe - A brightly colored magnesium fueled flare blinking with repetitive flashes.
• Wheel (Saxon) - Tubes that create a spinning wheel of sparks.

A basic theatrical effect, designed to create a jet or fountain of sparks, is referred to as a gerb. A gerb consists of a sufficiently strong and non-flammable container to hold the pyrotechnic compound. Typical pyrotechnic formulations consist either of flammable materials such as nitrocellulose and/or black powder or a mixture of a fuel and oxidizer blended in situ. A plug placed at one end of the container with a small orifice, called a choke, constricts the expulsion of the ignited pyrotechnic compound, increasing the size and aggressiveness of the jet.

Various ingredients may be added to pyrotechnic devices to provide colour, smoke, noise or sparks. Special additives and construction methods are used to modify the character of the effect produced, either to enhance or subdue the effect; for example, sandwiching layers of pyrotechnic compounds containing potassium perchlorate, sodium salicylate or sodium benzoate with layers that do not creates a fountain of sparks with an undulating whistle.

In general, such pyrotechnic devices are initiated by a remotely controlled electrical signal that causes an electric match, or e-match, to produce ignition. The remote control may be manual, via a switch console, or computer controlled according to a pre-programmed sequence and/or a sequence that tracks the live performance via stage cues.