Tuesday, September 9, 2008
Multi shot barrages (cakes) come in many sizes and shapes. Do not underestimate the power of this group of fireworks. Careful attention to detail is required when setting these up.
They can produce considerable forces when firing. For this reason they must be placed on stable and flat ground. Where this is not achievable, wooden boards may be required to form a firm base. These are held in place with stakes and Straps or Ties. This provides a firm base for the firework to recoil against, thereby reducing the possibility of distortion or breaking internal fuses thus breaking the fuse chain, or misdirection of projected pyrotechnic items. They can also be buried to half their depth in soil or sand if required.
Make sure that they cannot topple over and secure them to two or three stakes set around the box with straps or ties. They should be slightly angled away from the spectators and the underside of the box packed out with wooden boards.
The larger cakes are already wrapped in plastic but it is good practice to further protect them in damp or wet conditions at fireworks displays.
The fuses on the Chinese cakes can be unreliable and should be replaced with green delay fuse (PIC). Insert some quickmatch with the end bared directly into the first tube of the cake to replace the original fuse, and connect a length of green delay fuse to this. Some cakes are susceptible to blowing up if badly constructed.
Remember – a barrage cake may have as many as twenty or thirty 2.5” (65mm) shells in one box!
Placing and loading mortars
As a Rule 1st Galaxy Fireworks Ltd use racking systems for 2.5” (65mm) – 5” (130mm) Mortar Tubes, these Racks can fix together to form a solid structure. Or where safety requires distances between them, we can stake them in Two Places (at opposing diagonal corners). These are placed long ways onto the crowd, ensuring that they cannot fall over in that direction.
Larger Mortars are secured With Three Large Stakes, they can either be buried to cover the Shell itself, e.g. a 6 inch shell would be placed in a 6 – 8” hole, thus the shell is set slightly in the ground. This offers both a stable surround, and some protection should the delay blow, and the lift charge and break fire within the tube at the same time. Sand bags can also offer protection from such an occurrence if used to surround the base of the tube.
Stakes: The use of stakes, preferably strong wooden, or purpose made racks are the only practical methods of safely setting up mortar tubes
Ensure that stakes are driven firmly into the ground before the fireworks are attached to them.
All stakes must be angled by no more than 15 degrees away from the crowd, depending on site conditions
Where stakes are used to obtain a fan effect, from Roman Candles for instance, then these must not lean over from the vertical by more than 15 degrees, i.e. 30 degrees between the two.
Where Set Pieces are secured to a stake(s), attach them to the rear of the stake. This applies especially to shell tubes and Roman Candles. The only exceptions to this rule are Wheels which will be on the front of a pole but this will still be secured to the rear of a stake.
Make sure that the fireworks are firmly attached to the stakes using string, nylon cable ties or straps. Each one must have at least two separate fixings at the top and middle points. Larger fireworks will require more. Do not over tighten nylon tie fixings as this may cause a restriction in the tube.
Stakes must not extend beyond the opening of the firework and care must be taken not to split open the top of the stake. Good quality, not split, 50mm x 50mm wooden are recommended for most fireworks although lighter gauge stakes may be used on the small candle boxes, Steel angle iron stakes are ideal as long as they are not too flimsy. A selection of lengths will be required for the different size fireworks.
Make sure that the ties are not too tight. This could restrict the bore of the firework, particularly candles.
It should be stressed that the procedures and information set out in this course are to be strictly adhered to.
A shell is launched from a mortar tube. These are made to withstand the pressure created when the lifting charge explodes. It is therefore essential that the following initial considerations are taken into account.
• Is the tube in good condition and dry and that the bung is firmly in place
• Is the tube the correct size for the shell
• Is the tube long enough
• Is it made from a suitable material
All tubes should be carefully checked to make sure that they are not damaged, damp or obstructed in any way.
The shell must be a good fit in the tube. If it is loose the effect of the lifting charge will be to partially bypass the shell and produce insufficient pressure to lift it high enough into the air. This can result in a “low burst”.
If it is too tight there is danger that the shell will not clear the tube when the lifting
charge detonates, resulting in the tube being split and the shell exploding at or near ground level. This can result in a “low burst”. This will also make the likelihood of fragments from the tubes an additional danger.
This is particularly important when using top fused shells as the connecting fuse
between the delay and the bursting charge may be damaged. This will cause the
shell to explode but not the lifting charge.
It is important that mortar tubes are made of materials that will not fragment.
Suitable materials are cardboard / fibreboard, high density polyethylene, heavy duty UPVC. If in doubt then don’t use them.
NEVER use tubes constructed from steel or hard brittle plastics such as drain pipe.
Fibreboard tubes that become wet lose a great deal of their strength and will not recover. Always ensure that tubes are protected from the weather and stay dry. Shells to be put into plastic tubes are best put in a poly bag first – plastic sweats!
Shells generally range in size from 2” (50mm.) to the massive 16” (400mm.) finale shell. Common sizes are 3” (75mm.), 4” (100mm.), 5” (125mm.), 6” (150mm.),8” (200mm.), 10” (250mm.), 12” (300mm.). Single tubes are generally used for 150mm. shells and larger.
Before loading the shell, make sure that the tube is empty.
The shell should be a comfortable sliding fit down the whole length of the tube and must rest at the bottom. Make sure that you are using the correct size tube for the shell. Check that the shell is the correct way up. Sometimes the string loop on the shell can break away causing the shell to hang upside down. Do not remove strings.
Setting up mortar tubes
Where mortar tubes are not available in specially constructed racks, they must be secured to a stake that is driven well into the ground or an appropriate steel or timber frame. A small piece of timber must be inserted between the tube and the ground to transmit the force of firing. Otherwise the base of the tube could be blown off.
The tubes must be positioned at a safe distance from the spectators in the event of a tube failure. The firers must wear the correct PPE and allow sufficient time to get to a position of safety.
They must be fixed in at least 2 separate positions using straps, nylon ties or strong sisal string and the tube must be positioned on the far side of the stake, angled away from the spectators. Check that there is sufficient room between tubes or tube racks.
Make sure that the tube is completely clear of debris from the previous display
firing before lowering the shell into it.
The shells are lowered into the tubes using the long fuse. Handle them with care, they are fragile. The larger shells (10” and upwards) may have a string for lowering. The fuse is not strong enough to lower these. Some shells need the string to assist flight.
The lifting charge is usually contained in a paper cone at the bottom of the shell. This may not be obvious when using plastic shells so check that they are the right way up!
The shell should be a comfortable sliding fit down the whole length of the tube and must rest at the bottom. Make sure that you are using the correct size tube for the shell.
Shells with ancillaries / tails & some double break shells may have a protective wrapper over the top of the additional ignition point. These are for protection during transit and must be removed before inserting into the tube. Often coloured red.
If it does not slide in – DO NOT FORCE IT.
NEVER RE-LOAD A TUBE DURING A FIREWORK DISPLAY
If possible set up the Finale first, protecting it from possible sparks from other pieces by setting up and covering with aluminium foil.
Cover each piece with foil or plastic bags, as necessary.
Monday, September 8, 2008
Shell Batteries / Shell Strings
These are generally used for 75mm. and 100mm. shells fired in sequences. They are usually used in groups of 6 shells for 75mm, and 5 for 100mm.
Such sequences are normally placed in racks specially designed for the purpose.
This allows the shells to be fused together, normally with a time delay between each shell using green PIC. Certain Maroons must not be placed in racks. Always load into individual tubes.
The racks must be secured using wooden stakes or steel pins. If using steel pins
(road pins) or angle irons, then the sledge or club hammer must be protected from the pin to avoid sparks - a piece of cardboard or wood should be sufficient for the purpose. Non- ferrous hammers are available, but are extremely expensive and difficult to procure. If setting up close to where other fireworks have already been prepared, consider placing all the stakes out before fixing the tubes.
Make sure that all fuses are protected whilst securing the stakes and that the racks are angled away from the spectators.
All match fuses must be secured to the top of the mortar tube to prevent it being lifted off by an adjacent shell when fired. This can be difficult to achieve on plastic tubes as they tend to stay damp. In such cases wipe them dry with a rag or paper towel beforehand.
To secure the shell leaders (quickmatch leaders) to the racks use wooden battens tied down using nylon zip ties to pinch the leaders onto the rack frame. You can also use a zip ties on individual leaders, but when using a larger number of shells this is fiddly and time consuming so the former is usually preferred. Another method is to tape the leader down, but this is usually a last option and used if zip ties etc run out as the tape tends not to stick to the racks, but is useful when attaching leaders to the cardboard tubes, simply ensure the surface is as clean as possible giving the tape chance to stick well.
Never use a Stapler to secure shell leaders onto a wooden frame; this can result in premature ignition.
This applies to both batteries and single tubes as the quickmatch fuse can blow itself out when bent over the edge of tubes.
It is important to ensure that the brown paper quickmatch fuse is completely inside the mortar tube and covered as it is particularly sensitive to damp.
The paper fuse will need to be joined to a length of waterproof quickmatch which can be left outside the tube.
Some shells may be pre-fused at the factory. They must not be carried in the tubes in vehicles but unloaded before transport and re-loaded at the display site.
Maroons and Mines
Treat as for shells. Never put maroons in racks. They contain flash powder and if one blows the blast will destroy the whole rack.
As a rule Britannia Fireworks do not use Single, Large Rockets in our Displays, but on occasion we are requested to do so. If the site is suitable etc.. we take into account the following :-
The major consideration when setting up rockets is that the empty tubes and sticks will not fall onto spectators. It may seem obvious but the crowd are going to be looking up into the sky! This is where the debris will come from.
Before any firework display it is vital that the wind direction is checked. This is particularly important when considering where to fire rockets. We have already made reference to the fact that rockets turn back into the wind. Plenty of space is required to fire them and an adequate “fall out zone” must be available.
Rockets should be set up in racks specially designed for the purpose. These can take the form of steel tubes welded onto a frame. One alternative is to construct a timber frame made from 1 ½ “ x 1” timber (38 x25mm). The sticks can then be dropped into such suitable guides as large screw eyes, saddle clips, staples of 12mm. diameter or plastic tubes set into spring clips.
Check first of all that the stick of the rocket is firmly fixed to the body and that the stick is not broken or split. Make certain that the rocket is free to rise with no obstructions.
Most rockets have fuse caps. These must be removed for fusing but delay this as long as possible to avoid damp. Rockets are very often fired in a sequence and will therefore need to be fused together. Use green fuse and secure this with tape to each rocket fuse. Be careful the green fuse does not fall away from the rocket as it burns.
Remember to remove all plastic waterproofing before firing rockets!
Rockets – Flights
These are smaller rockets which are fired in groups of 10 or more at the same time and may be fired from a metal cone, an 8” (200mm) tube or a specially constructed box.
Flights are fitted with instantaneous match fuse, unlike their bigger brothers which have delay fuses.
The method for fusing flights is to ensure that all of them fire together. A length of brown fuse or more commonly quickmatch is attached to two rocket fuses and a piece of green fuse is finally attached to the brown or quickmatch to act as the delay fuse. The spread of fire from each fuse will ensure that they will all fire simultaneously.
Roman Candles, single
These fireworks must be securely fixed to a stake using at least 2 ties, or set firmly in sand or earth. It is important to make sure that they cannot topple as the balls of fire and effects are thrown to a considerable height. When using wire, care must be taken so as not to over tighten and restrict the bore of the tube.
These are very often used in pairs or groups of three to create spectacular effects in fans. In this case they should be fixed as before to specially constructed frames which are in turn attached to stakes. They should be angled away and fixed on the side furthest away from the spectators. If frames are used it will determine the angle of the candles automatically, but if in sand or earth then the maximum permitted angle from the vertical must be no more than 15 degrees.
Candles are fused together using quickmatch. The end of the quickmatch is exposed and is inserted into the open end of the candle. A further short length of black match is used in the end of the candle to aid ignition. All fuses are then secured to the candle using tape. All fuses are then brought to a central point and a 5 second delay using green fuse is finally connected.
Bundles of candles
Small Roman Candles can be tied together to form a bundle of 7 or 19. The bundle is tied together using strong tape or wire provided it is not too tight. These are then secured to a stake or special frame as previously described.
They are fused together by exposing the fuses and laying a generous quantity of black match over the top of them. A delay fuse is attached to the black match and then the top is completely covered with tape to waterproof the items, leaving only the green delay fuse exposed. These can also be linked to others.
Wednesday, August 20, 2008
An incomplete electrical circuit
The United Nations publication for classification and testing of dangerous goods
The component of an explosive that supplies oxygen for the reaction of the product
A colour break with palm tree core
An electrical circuit in which the current is divided between several igniters. Less easy to test for breaks.
Commonly used to cover shells to enhance their burst
A shell of fewer stars that creates a pattern rather than a sphere
A shell whose stars do not leave any trails
Plastic Igniter cord
A specialised type of firework which travels to and fro along a horizontal rope
Raw match enclosed in a paper or plastic tube
The central core of a shell. Often a complimentary or contrasting colour to the main burst
A thin walled tube filled with slow burning composition used to light other fireworks
Composition used to produce force e.g. A rocket motor
Slow burning lighter for small fireworks
Generic term for any item which react in a self sustaining chemical reaction and generally produces a light effect. Pyrotechnic articles are different to fireworks and generally are used for stage and theatrical uses
Raw match enclosed in a paper or plastic tube
Apparatus for firing rockets or mortar tubes
Shells containing long burning stars that fall all the way to the ground.
Black powder coated thread used for linking fireworks
Usually a cylinder shell with timed bursts at regular intervals
An aerial shell that produces symmetrical rings of stars often have a rope tail to control orientation of the break
Often a tail effect on a shell but can be external attachments to a shell that break off during the rise to create special effects
Aerial effect propelled by a motor
A device for firing flight rockets
The power unit behind a rocket. Typically made by pressing black powder into a choked tube
A cardboard tube with a stack of timed comets or bombette units
A shell in the form of a sphere usually containing coloured stars
The area around a fireworks display site between the spectators and fireworks. Not including a fall out zone
Report or loud bang
A chrysanthemum break with an outer ring of a contrasting colour
A bar with centre pivot with drivers at either one or two ends which make the bar spin on a central point.
A whistle unit with a hole through the centre. This increases the burn speed and therefore the sound
The pattern in which fireworks are detonated in a display
A circuit arranged so the current runs through each igniter in turn. This enables and breaks to be detected
A spinning tube used in candles and shells. Usually with a report unit
A ground firework. Generally static
The most spectacular of fireworks propelled with a lifting charge from a mortar and a bursting charge that charge to a star composition in the air after a predetermined delay
See Delay fuse
Shell of shells
An aerial shell that contains smaller shells ignited when the main shell bursts and subsequently produces small secondary bursts
The accidental completion of a circuit which causes the current to not flow through the igniter
The single functioning of a roman candle or cake
Air suspension of particles from incomplete combustion of a composition
A powder containing nitro-cellulose and nitro-glycerine as it does not produce much smoke
Typical effect caused by incandescent particles ejected form the surface of a burning composition
Wire coated with pyrotechnic composition that gives off small sparks
A shell containing a small number of large stars producing a symmetrical burst. Sometimes called octopus shells
A comet with an internal charge of flash powder which when ignited splits the comet into several pieces.
A pressed unit of composition usually spheres or cylinders used in shells, mines, rockets and roman candles
The holding of fireworks prior to their use. Premises must be licensed for amounts above a certain quantity
A pulsing on off star effect fired from candles and shells and ground based effects
A comet star secured to the outside of a shell to give a tail to the rising shell
Tiger tail shell
A shell made up of a solid ball of composition to produce a substantial tail effect. Sometimes with a small shell break
A silver metal used in the production of maroons and gerbes
A shell where the shell delay is lit separately from the lifting charge. Often found in large Maltese shells
The process of consigning a load of fireworks. Subject to heavy legislative control
Documentation required when transporting fireworks of any quantity. Transport emergency card. Provide information for emergency services
A large tail unit often used on palm and willow shells
The assignment of a packaged firework into the UN classes for fireworks
UN compatibility group
The G or S of 1.3G or 1.4S. The compatibility group indicated what a particular item may and not be transported with
UN Hazard code
See UN number
A complicated mark assigned to a particular packing box for dangerous goods
A four-digit number assigned to hazardous goods. Explosives always start with a 0 e.g. 1.4G fireworks are UN 0336. Used to identify a dangerous item in the event of an emergency
A mass firing of rockets or shells
Aquatic fireworks e.g. shells or water gerb
A floating gerb with a weight and cork float.
See Aquatic shell
A curtain of coloured or silver sparks that falls vertically. Composition is made from an aluminium alloy
A rotating piece attached to a post in the form of a saxon bar or wheel with driver units
A tube containing composition of potassium benzoate and potassium silicate. On burning the composition creates oscillation in the tube and creates a whistle effect which is amplified in the tube
A shell containing charcoal based stars with a long burn time which often fall to the ground
Tuesday, August 19, 2008
The UN Classification of Fireworks packaged for transport that poses a mass explosion hazard.
The UN Classification of Fireworks packaged for transport that poses a projectile hazard
The UN Classification of Fireworks packaged for transport that poses a fiery projectile or thermal radiation hazard
The UN Classification of Fireworks packaged for transport that poses a limited hazard
The UN Classification of Fireworks packaged for transport that poses a very limited hazard with minimal effect if ignited.
Regulations covering all drivers of explosives vehicles over a certain net weight of explosives
A firework that has its main function above ground level mainly shells, roman candles, mines and cakes
A shell that is designed to function at altitude
A shell that is designed to function on the surface of water
A mine that is fired from a mortar with only a small casing to create minimum debris
Blackmatch without a sleeve
A combination of fireworks designed to be fired simultaneously
A group of roman candles grouped and fused together for increased effect or duration
Coloured flare usually made up from loose packed composition
A cotton thread coated with blackpowder in its raw state. Sometimes cased in a paper tube
A composition of potassium nitrate, charcoal and sulphur in the proportion of 75:15:10 widely used in fireworks manufacture as a propellant and the basis for compositions containing metal powders. Blackpowder does not detonate on ignition but merely burns very fast
A shell that fails to break. Potentially very dangerous
An effect of periodic burning giving the effect of flashing or strobe
Spanish for little shell. Usually found as part of roman candles or cakes and occasionally in mines or sub components of shells
The normal method of igniting a shell. The delay is ignited which then lights a delay fuse on the shells. Also used for cakes when the fuse runs round the base of each tube and enters via a small hole
British Pyrotechnic Association. Trade organisation concerned with all areas of firework safety and use in the
A burst of a shell or bombette unit. Shells can either be single or multibreak units
The standards set for consumer fireworks for labelling and construction. All consumer fireworks must comply with BS 7114 part2 1988
Long burning star that burns bright but not as long as a kimuro
Always used at one end only of a tube or mortar. A composite or solid wooden disk the same size as internal diameter of a tube and usually nailed and glued into the tube to keep secure. Bungs are often made of compressed clay for items including cakes and roman candles.
An internal charge of a shell or bombette unit that breaks the shell open at a predetermined height. Made from gunpowder or flashpowder
A burst of a cylindrical tube from a central point which creates an effect that looks like the wings of a butterfly
Colloquial term for a multi shot battery
The inside diameter of a firing tube or mortar
An aerial shell containing several shells that explodes at the same time. Also a battery of reports from china
The tube that contains firework composition
The traditional name for a wheel. The name given because of St.Catherine who was martyred on a burning rotating wheel
A method of fusing several firework elements together e.g. shells
A roll of many hundreds of individual cracker units which produces a machinegun report effect when hung up. Traditionally used for Chinese celebrations
The narrowing of a tube usually for fountains or rockets by means of squeezing the tube or the insertion of a clay bung
A spherical burst in which each star leaves a visible trail
A completed electrical circuit. i.e. A ready to fire circuit
A shell containing large stars usually gold, silver or crackling to produce a palm tree effect. Usually fitted with a tail to produce the trunk effect
A solid unit of composition usually used in roman candles. The unit is completely self consuming so is useful for site where fallout is a problem
A term used for all pyrotechnic mixtures. More specifically it is a list of ingredients in a particular mix. All compositions contain an oxidant together with colour or effect ingredients.
A specialised fountain in the shape of a cone. A burning cone will increase the height of the spark shower as it burns as the surface area that burns is increased.
Banger unit also see Chinese cracker
An effect containing hundreds of sharp bangs thrown off a low intensity comet. Most crackle compositions contain lead or bismuth oxides
A piece of thin raw match used to facilitate the ignition of a shells internal delay fuse. Usually made from splitting or punching the delay fuse
See Splitting comet
Two stars in a single tube with a central bursting charge
A chrysanthemum break with longer burning stars that fall to the ground. Often produced to have coloured tips at the end.
A plastic ring with driver units that rotate and flies vertically. Double acting versions are available which ascend drop sand then re ascend
Usually European and commonly a stack of shells that are timed to break in a sequence.
A shell with larger and brighter stars than peony breaks
Explosive propagation which is faster than burning but is not detonation
Pyrotechnic composition that burns at a predetermined rate and used for timing within or externally between fireworks
A pyrotechnic composition designed to delay before functioning the next explosive device. Most commonly used in shell spikes as they rise into the air.
The are used for rigging and including the safety and fallout area
A specialist gerb with more power whose primary purpose is to rotate a wheel. Often including titanium.
Department of Trade and Industry responsible for aspects of sale of fireworks to the general public
The Explosives Industry Group of the Confederation of British Industry. Its main purpose is liaison with government on safety and legislative matters
The process of firing a displays electrically.
An electrically ignited match head commonly used on electrically fired displays. These are not to be confused with detonators
An electric igniter
A proposed standard for fireworks across Europe (CEN 212) currently being adopted across
Any material that is capable of undergoing a self contained self-sustained exothermic chemical reaction at a rate that is sufficient to produce substantial pressures on their surroundings thus causing physical damage. All fireworks are classified as explosives
The progress of fire from one explosive component to another.
A safe area designated for any debris fallout from a display. This must be selected with climatic conditions in mind.
A rapid firing pre fused sequence fired at the end of a display
An explosive assigned to UN numbers 0333 to 0337.
A pyrotechnic device designed to emit coloured light.
A rocket containing a flashpowder charge that produces a loud report after its ascent
A small rocket. Usually fired in large numbers simultaneously from a tube or cone
A spark effect produced by incorporation of coarse metal powders, usually aluminium
A device containing pyrotechnic composition in a tube which is usually choked.
An arrangement of mines, fountains or roman candles arranged parallel with the spectators and fired simultaneously
Means of transferring fire to a firework
A protective cover for the initial fuse of a firework. Often coloured orange
A firework of limited power for use in restricted outdoor areas. Category 2 fireworks.
A thick walled tube filled with composition and having a choke. Emits shower of sparks
Production of molten composition droplets which react with air to produce a glittery effect. Similar but different to strobe and flitter
Pyrotechnists term for black powder.
A multibreak shell comprising of colour breaks with timed detonation
Japanese for fireworks translated as 'flowers of fire'
An explosive that is capable of exploding when unconfined
The British Health and Safety Executive. Enforcement and legislative body.
A thick walled tube filled with composition with a specific burn rate so as to produce a humming sound
A shortened term for an electric igniter
Also called pic. This is available in several burning speeds. Often used to time link fireworks
The initiation of burning of a pyrotechnic material
Devices of very limited power suitable for indoor use
Japanese style shell
A spherical burst shell. Has perfect symmetry and patterned displays.
A long burning star usually silver or gold. Falls for long distances and colour changes at the end of its flight
A strong brown paper used for finishing shells and capping.
Small thin walled tube containing coloured composition.
A message or logo made from wooden framework and lances fused and positioned in a specific manner
An initial fuse of a shell from its fuse to the lifting charge
A charge beneath an aerial shell that propels the unit into the air
A rocket designed to travel along a wire or rope
An explosive device that produces a loud report
A generic term for quickmatch or black match
A lifting charge with either comet stars or bombette units fired from a mortar tube.
A roman candle which ejects min mine effects rather than comet or bombette units
A failure of a firework to perform as designed
A tube used to fire a shell or mine. Open at one and sealed with a bung at the other
A mine fired from a mortar
A specialised system for firework ignition using a shock tube. High-speed simultaneous ignition can be achieved.