Firework Displays & Safety Dave White Tony Wilkinson

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  • Firework Displays & SafetyDave WhiteTony Wilkinson

  • Just common sense innit?

    Assessing RiskRegulationsKnowledge of the subjectMorbid Imagination Before we move on

  • Lack of common sense!

  • Todays TopicsRegulations etc.Black Powder (gunpowder)DeflagrationFirework TypesEstimating RiskPlanning an eventFiring a showDemonstrations

  • Regulations etc.Categories of Firework (BS7114) Category 1 ("indoor") fireworks are for use in extremely restricted areas.Category 2 ("garden") fireworks are for use by the public in their gardens. Safely viewable from 5m, no debris beyond 3m.Category 3 ("display") fireworks are for use by the public in larger displays. Safely viewable from 25m, no debris beyond 20m.Category 4 ("professional") for sale only to fireworks professionals. They have few restrictions, default category for untested fireworks

  • Regulations etc.UN Hazardous Materials Class 11.1 Mass Explosion Hazard1.2 Nonmass explosion, fragment-producing1.3 Mass fire, minor blast or fragment hazard1.4 Moderate fire, no blast or fragment: a consumer firework is 1.4G or 1.4S1.5 Explosive substance, very insensitive (with a mass explosion hazard)1.6 Explosive article, extremely insensitive

  • Regulations etc.Firework Categories & ClassesConsumer FireworksUsually Cat.3 1.4GDisplay FireworksUsually Cat.4Mostly 1.3GLarge shells now 1.1G(ADR)

  • Black Powder (Gunpowder)IntroductionUsed for:Propellant (small grain e.g. Gun)Propellant (large grain e.g. Rocket)Explosive (burst charge)Fuses, delays etc.

  • Black PowderSolid Grain SOLID GRAIN LIQUID GAS FLAME

  • Black Powder Grain Burn

  • Black Powder Deflagration

  • Black Powder Confinement

  • Black Powder Confinement Failure!3,000 C50,000psi

  • FlashPerchlorate and atomised AluminiumLoud reportsHard Break shells and rocketsHigh Brisanceexplodes with little confinement>10g = 1.1G

  • Some types of Firework

  • Firework: RocketConstructionStars(with burst charge)

    BP Grain

    Nozzle

    Balance stick

    Launch tube

  • Firework: RocketFailure modesCracked Rocket Motor

  • Firework: RocketFailure modesGroundburst

    AlsoFailure to fly

  • Firework: RocketEffect of windCofGwindAngling away from wind make it worse!

  • Fireworks: GerbsFountainsFountain with sparksKimbolton 7lb GerbSolid or compressed grain

  • Fireworks: CakesMulti-shot BatteryCrackle RedExplosive (flash)Red Flare (delay)Propellant (BP)Fuse

  • Fireworks: CakesMulti-shot Battery

  • Fireworks: CandlesRoman CandleFelt wadFuseDelayMulti-shot19mm 65mm +Sidewall can failStake, Board or Box

  • Fireworks: ShellsIntroduction 3 , 4 and 5 (75,100,125mm)6 and up 1.1G

  • Fireworks: ShellsConstruction~100m/sec ~300mph!50m+ burst

  • Fireworks: ShellsFailure ModesNo Lift (or zero delay)FlowerpotdetonationPoor LiftLow Break (going up)Long or failed delayLow Break (coming down)Black Shell

    Causes: Malfunction, Jam, Loading error

  • Fireworks: ShellsCalculating DistancesRule of thumb:25m + 10m per shell inchOther Variables:Mortar angleWind speed & directionShell spinMortar type (esp. steel)Note:Normal safety distances do NOT account for disrupted racks4 Shell

  • Fireworks: ShellsCalculating Distances4 Shell 100m burst diameter, burst at 6m, 230m from launchMortar fallen to 75 degrees from vertical

  • Fireworks: Fuse & IgnitersPIC Green / BrownWASAGPipe Match (green)Electric matches (dets)

  • PPEClothingHard HatEye protectionEar protection (or not)Gloves (or not)Dont forget: Torch and Several lighters!

  • A Firework ShowPlanning the EventSite VisitsSafety DistancesRoads, Buildings, AirportsResponsibilitiesEvent OrganiserMarshalling requirementsNotification: Police, Fire, CAA (and any other affected parties)Budget etc.Method StatementRisk Assessment

  • A Firework ShowPlanning the DisplayCheck material (if possible)Firing OrderEquipment RequirementsRacks, boxes, boards etc.Material PreparationFusingWaterproofingTransportADR

  • A Firework ShowSite SetupEvent Organiser Safety DistancesWind DirectionPerimeters and MarshallingLayout in firing orderSite fusing / wiring

    Set PiecesSmall CakesCandlesLarge CakesShellsAudienceDrop Zone

  • A Firework ShowSite SetupDriffield Showground 24th June 2006

  • A Firework ShowSite SetupHull University Union May 2004

  • A Firework ShowFiring the DisplayFiring OrderGafferWalk-thruDecision to fireKeep lookoutCheck for dudsClearing Up

  • More Information:Training courseswww.kimboltonfireworks.co.ukwww.fantasticfireworks.biz

    www.fireworks.co.ukLots of links at Fireworks magazine site:

  • Outdoor DemonstrationsExample equipmentTypes of fuseBlack Powder and confinementFire Fighting

    IntroductionGood afternoon everyone, Im Tony Wilkinson of Starfire Pyrotechnics and this lecture is intended as an introduction to the science of Pyrotechnics, thats the chemistry, physics and mechanics of fireworks.Is there anyone here who thinks Ive come along here to just blow some things up just for the sake of it?Well well try not to disappoint you!Seriously

    Safety BriefingNo-one forward of the line, unless specifically asked to do soThere may be the odd bang here and there, though I will always give some warning in case theres anyone of a particularly nervous dispositionI should also mention that this might make an appearance .. GUNits a blank-firing replica of an 1851 Colt Navy black powder pistol, not a real gun.There might be some smoke, but hopefully the extractor will take care of that.We wont be generating any particularly toxic fumes, so you shouldnt choke to death !In the very unlikely event of fire, we have two other members of Starfire here:Dave WhiteAndKevin FordWho will act as fire marshals. To avoid any misunderstandings during demonstrations, an order to evacuate will only be given by Dave, Kevin or myself. Having said that, dont worry we do know what we are doing, we are professional firework display operators who take safety very seriously. Weve done over 50 shows in the last 5 years with no incidents whatsoever.Last, but not least, I must stress that some of the things youll see this afternoon are in theDONT TRY THIS AT HOME categoryFirstly, they may be extremely dangerous unless you know exactly what you are doing and have the right safety equipmentSecondly, any manufacture, modification or disassembly of any firework item is strictly illegal.And it is still the case that a conviction under the Explosives Act would remain with you for life, meaning you would never be able to work in explosives or fireworks and never be allowed a firearms licence.

    Safety BriefingNo-one forward of the line, unless specifically asked to do soThere may be the odd bang here and there, though I will always give some warning in case theres anyone of a particularly nervous dispositionI should also mention that this might make an appearance .. GUNits a blank-firing replica of an 1851 Colt Navy black powder pistol, not a real gun.There might be some smoke, but hopefully the extractor will take care of that.We wont be generating any particularly toxic fumes, so you shouldnt choke to death !In the very unlikely event of fire, we have two other members of Starfire here:Dave WhiteAndKevin FordWho will act as fire marshals. To avoid any misunderstandings during demonstrations, an order to evacuate will only be given by Dave, Kevin or myself. Having said that, dont worry we do know what we are doing, we are professional firework display operators who take safety very seriously. Weve done over 50 shows in the last 5 years with no incidents whatsoever.Last, but not least, I must stress that some of the things youll see this afternoon are in theDONT TRY THIS AT HOME categoryFirstly, they may be extremely dangerous unless you know exactly what you are doing and have the right safety equipmentSecondly, any manufacture, modification or disassembly of any firework item is strictly illegal.And it is still the case that a conviction under the Explosives Act would remain with you for life, meaning you would never be able to work in explosives or fireworks and never be allowed a firearms licence.

    Now I could go on all day about any one of these, but Ive chosen a few of the essential elements for some detail:Burning / Deflagration / Detonationits all gotta burn somehow, so we might as well know why and how it burns !Not Combustion but Oxidation/ReductionBlack Powder (gunpowder) this is part of almost all fireworks and is used as a propellant (like in a gun or in a rocket motor), to make delays and fuses and as an explosive.Effects are a bit complicated and, even now, the exact chemistry is still being argued about!like the strobe material I just showed you, they involve several separate chemical reactions going on at the same time so Ill skip this one for todayColours are essential in modern fireworks and, interestingly, have nothing at all to do with gunpowder

    Progressive Burning of ONE BIG GRAINTheres 3 important things here:Increased PressureIncreased TemperatureIncreased Reaction rate50,000psi = more than 1,500 times the pressure of a car tyre !!!!(thats about 350MPa )

    WHAT WOULD HAPPEN HERE ?WHAT WOULD HAPPEN HERE ?WHAT WOULD HAPPEN HERE ?WHAT WOULD HAPPEN HERE ?