Some suggestions for Fireworks Display Material Use Part 2

Shell Barrages – “Cake Boards”

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.

Shells

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.

Some suggestions for Fireworks Display Material Use

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.

shells.

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.

Rockets

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

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.

Glossary of Firework Names A-N

Item	Definition
1.1G	The UN Classification of Fireworks packaged for transport that poses a mass explosion hazard.
1.2G	The UN Classification of Fireworks packaged for transport that poses a projectile hazard
1.3G	The UN Classification of Fireworks packaged for transport that poses a fiery projectile or thermal radiation hazard
1.4G	The UN Classification of Fireworks packaged for transport that poses a limited hazard
1.4S	The UN Classification of Fireworks packaged for transport that poses a very limited hazard with minimal effect if ignited.
ADR	Regulations covering all drivers of explosives vehicles over a certain net weight of explosives
Aerial Firework	A firework that has its main function above ground level mainly shells, roman candles, mines and cakes
Aerial shells	A shell that is designed to function at altitude
Aquatic shell	A shell that is designed to function on the surface of water
Bag mine	A mine that is fired from a mortar with only a small casing to create minimum debris
Bare match	Blackmatch without a sleeve
Barrage	A combination of fireworks designed to be fired simultaneously
Battery	A group of roman candles grouped and fused together for increased effect or duration
Bengal	Coloured flare usually made up from loose packed composition
Blackmatch	A cotton thread coated with blackpowder in its raw state. Sometimes cased in a paper tube
Black powder	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
Blind shell	A shell that fails to break. Potentially very dangerous
Blinker	An effect of periodic burning giving the effect of flashing or strobe
Bombette	Spanish for little shell. Usually found as part of roman candles or cakes and occasionally in mines or sub components of shells
Bottom fused	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
BPA	British Pyrotechnic Association. Trade organisation concerned with all areas of firework safety and use in the UK
Break	A burst of a shell or bombette unit. Shells can either be single or multibreak units
British Standard	The standards set for consumer fireworks for labelling and construction. All consumer fireworks must comply with BS 7114 part2 1988
Brocade	Long burning star that burns bright but not as long as a kimuro
Bung	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.
Bursting Charge	An internal charge of a shell or bombette unit that breaks the shell open at a predetermined height. Made from gunpowder or flashpowder
Butterfly	A burst of a cylindrical tube from a central point which creates an effect that looks like the wings of a butterfly
Cake	Colloquial term for a multi shot battery
Calibre	The inside diameter of a firing tube or mortar
Cannonade	An aerial shell containing several shells that explodes at the same time. Also a battery of reports from china
Case	The tube that contains firework composition
Catherine wheel	The traditional name for a wheel. The name given because of St.Catherine who was martyred on a burning rotating wheel
Chain fusing	A method of fusing several firework elements together e.g. shells
Chinese cracker	A roll of many hundreds of individual cracker units which produces a machinegun report effect when hung up. Traditionally used for Chinese celebrations
Choke	The narrowing of a tube usually for fountains or rockets by means of squeezing the tube or the insertion of a clay bung
Chrysanthemum break	A spherical burst in which each star leaves a visible trail
Closed circuit	A completed electrical circuit. i.e. A ready to fire circuit
Coconut break	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
Comet	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
Composition	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.
Cone	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.
Cracker	Banger unit also see Chinese cracker
Crackle	An effect containing hundreds of sharp bangs thrown off a low intensity comet. Most crackle compositions contain lead or bismuth oxides
Croaker	See Screecher
Cross match	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
Crossette	See Splitting comet
Crossing stars	Two stars in a single tube with a central bursting charge
Crown	See Kimuro
Crown chrysanthemum	A chrysanthemum break with longer burning stars that fall to the ground. Often produced to have coloured tips at the end.
Crown wheel	A plastic ring with driver units that rotate and flies vertically. Double acting versions are available which ascend drop sand then re ascend
Cylinder shell	Usually European and commonly a stack of shells that are timed to break in a sequence.
Dahlia	A shell with larger and brighter stars than peony breaks
Deflagration	Explosive propagation which is faster than burning but is not detonation
Delay	Pyrotechnic composition that burns at a predetermined rate and used for timing within or externally between fireworks

Delay fuse	A pyrotechnic composition designed to delay before functioning the next explosive device. Most commonly used in shell spikes as they rise into the air.
Display area	The are used for rigging and including the safety and fallout area
Driver	A specialist gerb with more power whose primary purpose is to rotate a wheel. Often including titanium.
DTI	Department of Trade and Industry responsible for aspects of sale of fireworks to the general public
EIG	The Explosives Industry Group of the Confederation of British Industry. Its main purpose is liaison with government on safety and legislative matters
Electric firing	The process of firing a displays electrically.
Electric igniter	An electrically ignited match head commonly used on electrically fired displays. These are not to be confused with detonators
Electric match	An electric igniter
European standard	A proposed standard for fireworks across Europe (CEN 212) currently being adopted across Europe.
Explosive	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
Explosive train	The progress of fire from one explosive component to another.
Fallout zone	A safe area designated for any debris fallout from a display. This must be selected with climatic conditions in mind.
Finale barrage	A rapid firing pre fused sequence fired at the end of a display
Firecracker	See Cracker
Firework	An explosive assigned to UN numbers 0333 to 0337.
Flare	A pyrotechnic device designed to emit coloured light.
Flash rocket	A rocket containing a flashpowder charge that produces a loud report after its ascent
Flight rocket	A small rocket. Usually fired in large numbers simultaneously from a tube or cone
Flitter	A spark effect produced by incorporation of coarse metal powders, usually aluminium
Fountain	A device containing pyrotechnic composition in a tube which is usually choked.
Front	An arrangement of mines, fountains or roman candles arranged parallel with the spectators and fired simultaneously
Fuse	Means of transferring fire to a firework
Fuse cover	A protective cover for the initial fuse of a firework. Often coloured orange
Garden firework	A firework of limited power for use in restricted outdoor areas. Category 2 fireworks.
Gerb	A thick walled tube filled with composition and having a choke. Emits shower of sparks
Glitter	Production of molten composition droplets which react with air to produce a glittery effect. Similar but different to strobe and flitter
Gunpowder	Pyrotechnists term for black powder.
Hammer shell	A multibreak shell comprising of colour breaks with timed detonation
Hanbai	Japanese for fireworks translated as 'flowers of fire'
High explosive	An explosive that is capable of exploding when unconfined
HSE	The British Health and Safety Executive. Enforcement and legislative body.
Hummer	A thick walled tube filled with composition with a specific burn rate so as to produce a humming sound
Igniter	A shortened term for an electric igniter
Igniter cord	Also called pic. This is available in several burning speeds. Often used to time link fireworks
Ignition	The initiation of burning of a pyrotechnic material
Indoor firework	Devices of very limited power suitable for indoor use
Japanese style shell	A spherical burst shell. Has perfect symmetry and patterned displays.
Kimuro	A long burning star usually silver or gold. Falls for long distances and colour changes at the end of its flight
Kraft paper	A strong brown paper used for finishing shells and capping.
Lance	Small thin walled tube containing coloured composition.
Lancework	A message or logo made from wooden framework and lances fused and positioned in a specific manner
Leader	An initial fuse of a shell from its fuse to the lifting charge
Lifting charge	A charge beneath an aerial shell that propels the unit into the air
Line rocket	A rocket designed to travel along a wire or rope
Maroon	An explosive device that produces a loud report
Match	A generic term for quickmatch or black match
Mine	A lifting charge with either comet stars or bombette units fired from a mortar tube.
Mini mine	A roman candle which ejects min mine effects rather than comet or bombette units
Misfire	A failure of a firework to perform as designed
Mixture	See Composition
Mortar	A tube used to fire a shell or mine. Open at one and sealed with a bung at the other
Mortar mine	A mine fired from a mortar
Niagara falls	See Waterfall
Nomatch	A specialised system for firework ignition using a shock tube. High-speed simultaneous ignition can be achieved.

Firework Types & How They Work

Roman Candles

A more complex firework, consisting of a tube containing pyrotechnic units alternating with propellant charges. When fired, the units are thrown into the air in sequence from top to bottom. Different effects are obtained by using successive units of varying colour and form. Roman Candles may also produce sound effects during their trajectory, including a report at the end. Between successive projections, the candle may emit coloured sparks or flame directly from the body.

They are made up to 60mm calibre and can send stars up to nearly 200 ft. The candle must therefore be securely fastened to a stake or candle frame.

It should be noted that as each successive star has further to travel up the case of the candle, it takes longer to exit the tube and is therefore subjected to the lifting charge for longer. The quantity of gunpowder has to be progressively decreased to achieve the same height. Do not use damaged candles – there could be a blow out.

Whilst the styles or effects have remained more or less unaltered throughout their history, there have been alterations in the method of activity of achieving the delay between the successive stars.

a) The original Ruggieri design utilised green mix gunpowder and these candles will emit showers of sparks between successive stars. It should be noted that with the exception of any tube products that may be used, all the products are consumed and there is little or no fallout.

b) Typical Chinese candles are used in vast quantities in the fireworks industry. Here a continuous fuse runs down the side of the tube and is designed to burn for the duration of the candle. The delay between successive stars is achieved by alternating them with loose plugs of potters clay. During the course of even a modest display, a considerable amount of clay is thrown into the air. Beware!

c) In recent Years Britannia Fireworks Ltd have been using “Typical” Chinese Candles manufactured using similar ideas to the “Ruggieri Technique”, and showers are emitted between each shot, this has enabled slightly better timing and larger stars etc.

d) To overcome the problems of achieving synchronised firing, there have been two developments, the earliest being the substitution of the green mix delay with a felt plug with a pressed delay in the centre. These felt plugs return to Earth unburnt.

Shells

A shell is a hollow projectile containing an explosive charge. In Western Europe and the USA the shell may also have an attached lifting charge. It must be remembered that this practice is by no means universal and the presence of a lifting charge would not be considered a defining characteristic by firework technicians. (The presence of a propellant charge is considered a defining characteristic of a rocket!)

The shell is projected from a mortar tube by a charge of gunpowder (the lifting charge) to burst high in the air with whatever effect is incorporated in the shell.

The mortar tube may be made from cardboard, fibreboard or specific types of plastic.

The shells may be made from paper or plastic and are either spherical or cylindrical in shape. It is much easier to contrive multiple breaks or bursts with a cylindrical shell, whereas the spherical shells are required to produce spherical bursts, chrysanthemums, peonies.

Shells which explode with a loud report are called maroons or salutes

The diameter of shells used at Britannia Fireworks Ltd are generally anything from 2” to 12” and come in two types:-

a) Bottom fused and

b) Top fused

Bottom fused shells have their lifting charge ignited first. This in turn ignites a delay fuse to the bursting charge.

Top fused shells are fitted with a delay fuse to the bursting charge with a secondary instantaneous fuse to the lifting charge. These are perhaps a little more reliable as there is less risk of the delay fuse being blown out. These tend to be more cylindrical in shape. Care must be taken when installing top fused shells to avoid damage to this lifting charge fuse. It is also essential to ensure that the shell, as with all shells, is inserted into the tube the right way up. Damaged shells should not be used.

Shells can be extremely dangerous if they are not handled and fired in the approved manner. The exit velocity of a shell from the mortar tube could be in excess of 200 mph!

To appreciate the height and effect of a shell, the following can be used as a rough guide

If ‘x’ is the calibre of the shell in inches,

the delay to full height is ‘x’ seconds,

the height reached is ‘X’ x 100 feet,

the spread of burst is ‘X’ x 10 metres.

This will not always apply, however it can be used as a guide for most shells.

Mines

These can be regarded as similar to shells in the method of use. The important distinction between them is that the firework element is ignited in the tube and is already burning when it exits the tube.

The effect of a mine is therefore instantaneous from the spectators viewpoint and always lower, although heights of 100 ft. may still be reached. These produce effects of stars, bombettes, whistles etc. Special care must be given when loading the bag type mines.

It is sometimes extremely difficult to distinguish the difference between some cylindrical mines and cylindrical shells and there are even some spherical mines.

Multi Shot Barrages or “Cakes”

These fireworks known affectionately as “cakes” are actually a collection of other categories of fireworks grouped together in boxes and produce stars, bombettes, whistles, spinners, etc. They may vary in size from small packages up to large cardboard boxes which can be very heavy to handle.

A cake barrage may contain anything from say 36 x 2.5”” shells in light tubes, 100 x 30mm maroons or even up to 1000 roman candles one shot in each tube.

They are extremely powerful so please be careful! They need to be set up very carefully, with particular attention paid to the surface upon which they stand and secured to a series of stakes. Cakes should always be angled away from spectators.

It is important to ensure that they are the right way up! It is not unknown for them to be labelled upside down or even the larger ones to be packed into their boxes upside down. Please take note !

Due to the size of some Cakes and the calibres used, we recommend moving them at least 50 metres, and in some cases even further (refer to Britannia Fireworks Site Policy)

Cake barrages are boxes containing a number of separate items, fused together so that they are fired in sequence over some period of time, normally much longer than for a single firework. The items may be all of one kind, or a mixture, including small, shells, candles etc.

As with roman candles, once started, the firing continues automatically until the last item is reached.

Batteries are comprised of a number of fireworks, normally of the same type, grouped in a single layout, to be fired as a single unit, individually in sequence, or in any other combination. The effect is the same as from any one firework on its own, enhanced by sequential or multiple firing.