Pyrotechnics

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General principles of operation
A pyrotechnic is anything that involves fire, be it flame or explosion, however as we are covering fire (gas and other fuels) separately, here we will deal only with the explosive types. The most common ones that you will encounter are flashes, bangs, smoke, sparks, flames and occasionally bullet hits. They pretty much do as described, but they go by weird names.

Most pyros are usually set off electrically and almost always connected by a wire to a battery via a button and, for safety reasons, usually using the smallest size pyrotechnic possible. Very occasionally they can be set off by remote control.

Pyros can either be bought ready-made or they are made up for some particular effects.

Real explosions rarely look good on film, so often other elements are introduced to give added features, such as titanium for sparks, garden peat, cork and cement dust for lots of debris or petrol/diesel for a fireball.

A good technician will be able to make a great variety of different effects by varying the ingredients used.

First considerations
Because of insurance, crew sizes and equipment required, there will be extra costs involving pyro shoots, so do you really need to do it? A series of world events has had an impact on insurance costs, so charges may be dramatically higher than previously experienced.

Does your location/will your facility, allow you to do it safely, if at all?

Describe what you want in terms of the amount of fire, smoke, colour, sparks and speed of explosion. Are you able to achieve the desired effect?

Budget expectations
It takes a great deal of training and cost to become qualified pyro technician, this will be reflected in the price you are charged. Pyro shoots also require a minimum of two technicians, however small the job.

Often high-speed camera equipment is required and video playback facilities are essential.

Special insurance may have to be taken out.

Fire service support may also be required.

Questions to ask
Can I see your show reel?
How long have you been doing pyros?
What are your qualifications?
Have you personally / your company got PLI to at least £2M?
What choices do I have to achieve the desired effect?
Can I see an example of the pyrotechnic being fired?

Problems to watch out for and things to do
- Safety is paramount from preparation to clear up. So it is important to ensure that:
- The pyro technician is part of the planning process from the start and listened to.
- Unsympathetic location owners and locals have an accurate description of what will happen and clearance has been obtained, otherwise the second take may not be allowed.
- Mobile phones and radios are turned off as instructed by the effects crew as they can set off the pyros.
- Enthusiastic locals watch only from a convenient and safe location.
- Local authorities, such as the police and the fire brigade, have been informed.

Know the jargon
Black powder BP, gunpowder
Charge A ready to fire pyrotechnic
Det cord Detonator cord, cordtex, a type of high explosive initiator
Dets Generic term for bullet hits, also detonators for HE
Fast/sharp/hard Means the explosion happens much faster than gunpowder and does lots more local damage than gunpowder – ask your technician for details if you need to
Firing box The control box used for setting off pyros
Flame projectors Pyrotechnic devices which emit a jet of fire for a few seconds
Flash pot White or coloured flash with smoke
Flash powder A powder as used in ‘olde’ style flash photography puffs
Fuse Quick or slow fuse, usually used for visual effect, not for setting off pyros.
HE High explosive, very powerful, very fast/sharp/hard
Lift Use of the pyro to blast either debris or fuel into the air
Maroon Banger/sharp noisy pyros of various sizes
Match heads Small electrical ignitors for pyros-nothing to do with matches
Pyro Pyrotechnic, something which produces heat/fire/smoke/explosion etc when ignited/initiated.
Quick match ‘Cartoon comedy bomb’ style fuse.
Robotics Look like electrical wires shorting
Soft Slow (relative to HE) explosion usually Black Powder, (but BP can be modified to be
hard/sharp)
Squibs A small charge giving sparks, often used for bullet hits on objects
Ticket Means the BECTU issued pyrotechnic qualification or similar
Titaniun Added to gunpowder to make sparks