Safe use of Pyros

15 December, 2021

An Aid to pyro risk assessment


Geoffrey Joyce explains how to keep safe around Pyros this Xmas

From the beginning of time theatrical events have been calling for bigger and better effects in the form of flashes and bangs. Not so long ago a technician might sprinkle black ‘flash’ power on to a fine fuse wire and attaching to a car battery – to great effect. I remember providing a convincing flash for the local pantomime’s Fairy Godmother’s entrance, packing the flash powder into tissue paper made a wonderful effect with smoke rings! The Stage Manager could identify the person who had wrapped the tissue for that evening’s performance by the rising ring of smoke. Singeing eyelids is nothing new. Alarming times and potentially precarious times!

If you are a technician setting off stage pyrotechnics ask yourself when was the last time? Even if you’re ‘trained’ it might have been some years ago and skills fade. So, this is gentle ‘aide memoire’ to literally save your skin.
With very few exceptions, all pyrotechnics rely on the ignition of a continuous chemical combustion. This can either be spontaneous or over a longer period. Many pyrotechnics also have to produce large amounts of oxygen to work therefore once ignited they cannot be extinguished, until burned out, even underwater.
The deciding factor with pyrotechnics is safety. This must be given priority over every other aspect.

Consider these main ways of ensuring safety:-

  1. The devices must be designed and manufactured so that no risk is taken if used correctly, i.e., they function as intended, produce the desired effect, and produce the desired effect safely time after time. Remember Grubs come in different heights – don’t think a tall effect will look good. It might burn your header or an overhead cloth.
  2. The devices must be fired via a control system that has been manufactured with adequate safety features built in, both electrical and mechanical. Be careful of using tie lines – you never know what stray voltage may be larking there. It only takes a small amount of current (from comms or a cue light) to ignite a pyrotechnic!
  3. The user, i.e., the operator, should have enough experience and knowledge to ensure that, not only are the effects used correctly and safely to produce the effect required, but that they can cope with any unforeseen circumstances, i.e., they are competent users. Call me old fashioned but before loading the pod the holder should always be disconnected from its extension cable. I know of a number of technicians who have had their faces and hands burnt when plugging up through phantom firing and forget to remove or isolate the circuit! Don’t rely on the key alone. Recharging your pods during a matinee is the most challenging time – rushing around resetting – when show times are close to each other.
  4. The Firing control systems must be specifically designed for pyrotechnics. A minimum of three safety features should be incorporated before detonation of a device is possible. A key operated, power isolation switch, channel selection switch and a shrouded fire button. The key must always be kept with the person responsible for the pyrotechnics. It is only inserted when devices are to be fired. Never use the mains, all manufactured controllers today incorporate step down transformers.
  5. The golden rule on the positioning of controllers is that the operator must have a clear line of sight to all devices that are to be fired. For this reason, pyro operators are usually very close to the stage. The operator must be able to see all devices clearly and warn absent-minded personnel that pyro is to be fired. Maroon effects, for example, are usually set backstage.
  6. Ensure every member of the cast and stage crew rehearse with any pyro effect. Always have a second person standing by with fire blanket & extinguisher.

If pyrotechnics are called for in your production, amateur or professional, get a firing ticket and produce a suitable and sufficient risk assessment. The Association of Stage Pyrotechnicians (ASP) Will help with you to be a ‘theatrical Pyro firer’ and they will keep you up to date on the latest courses and on legislation.