This "book" is a compilation of many compositions gathered from across the internet. They have been copied them from various sources and as much of the original comments and tips have been retained, but they have not been tested. Therefore, we cannot provide much information on the performance, sensitivity, etc. of the actual mixtures. While the list contains several excellent compositions from reputed sources, it also contains several dangerous, outdated compositions. Please experiment cautiously and on a very small scale when testing any of the compositions in this database and test them thoroughly before using them in actual projects.
It is impossible to give a finite set of rules that will assure your safety in pyrotechnics. Described below you will find some of the most important and common ("everyday") things that should always be kept in mind when handling pyrotechnic compositions and chemicals. They apply to a wide variety of compositions.
But every composition is different. Some must be rammed or pressed to work properly. Others will explode when rammed. Some must be wet with water, others may spontaneously ignite when wet. Some mixtures are relatively safe to use by themselves but are extremely sensitive when used together (a number of well known 'incompatible' mixtures and chemicals are also listed below).
The point is: remember and think about the rules below; they are important, but realize any such list is inevitably incomplete. Accidents happen even in places where every conceivable safety precaution is taken. We don't guarantee your safety if you follow the rules below (also read the disclaimer), but merely say it is wise to do so. It'll increase your safety.
This document is provided for informational purposes only. The authors, contributors, and editors do not advocate the use of anything described in this document, and accept no responsibility for any harm that might occur as a result of acting on any of the information contained herein. Although good faith effort has been made to ensure the validity of the information contained in this document, no guarantees or assurances of accuracy are provided by anyone.
We accept no responsibility for persons harmed or injured or for any damage caused by devices like rockets, igniters, propellants etc. made on the basis of information presented on the following pages. Information presented herein is for informative purposes only. Also note that we have tried to give comments on safety aspects of the described procedures, but we may have forgotten things or have been inconsistent. Keep that in mind at all times. Use your common sense, and use more than one reliable source of information before doing anything.
There is often a short comment on the most obvious safety aspects of these mixtures, but these comments are inconsistent. Most of the details and standard precautions that should be taken during preparation and handling of the mixtures or their components are not mentioned. Procedures for safe mixing and other operations are considered known, and so is knowledge of combinations of chemicals that should never be used. The list does contain several dangerously sensitive mixtures. It is a must to obtain additional information from reliable sources on the safety of any of these compositions before experimenting with any of them.
All parts are by weight.
The abbreviation 'qs', which is sometimes used, stands for 'quantity sufficient'. In these cases the required amount is not very critical, and with some experience it is not hard to guess how much should be used. Additional percentages are given as '+x%', where the x% is a percentage of the total weight of the other chemicals.
Sometimes compositions must be stabilized: magnesium or magnalium must always be treated with potassium dichromate. Iron must always be coated with tung- or linseed oil. To all compositions containing both nitrates and aluminum, an additional +1% boric acid must be added. Compositions containing both sulfur and chlorates or copperammonium complex salts in combination with nitrates or chlorates are extremely sensitive and should never be used. Compositions containing aluminium or magnesium in combination with nitrates and chlorates should also never be used.
GENERAL SAFETY PRECAUTIONS
With that said, a list of some generally useful safety precautions in no particular order:
- Never smoke when handling chemicals or compositions.
- Keep all chemicals and compositions away from children and pets.
- Be sure you are familiar with all the properties of the compositions you work with. Thoroughly test new compositions for sensitivity, stability, and compatibility with other mixtures etc. until you are absolutely sure that the mixture is okay to use in your application and method of construction. Find out as much as you can about other peoples’ experiences with a particular mixture.
- Chemicals that need to be finely powdered before use should be ground separately in a clean mortar & pestle or a clean ball mill or tumbler. Keep separate equipment for oxidizers and fuels. For cleaning equipment used for fuels, a solvent or sand may be useful. NEVER GRIND EXPLOSIVE COMPOUNDS OR MIXTURES!!
- Use only non-sparking tools. Make your tools from wood, paper, aluminum, lead, or brass. Other metals and materials (especially steel) may spark.
- If storage is necessary, paper bags or wooden containers are good to use for storing mixed compositions. Avoid plastics, glass and metal. Store compositions dry and cool. In general, however, it is best to avoid storing compositions. Make as much as you will need in the near future and keep no more in stock than necessary.
- Never have large amounts of composition near you. If you must use larger amounts of composition in multiple items, store the bulk of composition in a safe place and bring only small amounts to your working place. Finished items should also be brought to a safe place immediately.
- Prevent contamination of chemicals and mixtures. Have separate tools for every type of mixture (i.e. black powder-like mixtures, chlorates, perchlorates, etc.) and clean them well with hot water and/or alcohol after use. Have different sets of clothing for working with different mixtures. Wash them every time after use (dust collects in the clothing). If it is possible, have separate rooms or - better yet - separate buildings for working with different types of mixtures/chemicals.
- Keep a clean working place. Fine dust easily spreads all over. Keep chemicals in closed cabinets or in a separate building. Mixtures should not be stored in the working place, anyway (see rules 6 and 7).
- Provide adequate ventilation. This is especially important when working with volatile solvents or (poisonous, flammable) powdered chemicals. Not only can you poison yourself, but vapor or dust may also ignite.
- Be aware of static electricity buildup. Ground your working table. Monitor humidity and keep it above 60% as a rule of thumb. This can be especially important in winter when preparing for New Years Eve (in the Northern Hemisphere, at least). Touch a grounded surface before you place things on it. Touch other people before handing over compositions or finished items. Wear cotton clothing and avoid synthetics (do not be tempted to wear fleece clothing if your working place is cold in winter). Simple things such as unscrewing a (plastic) bottle, unwinding some tape, or even moving your arm may accumulate enough charge on your body to ignite a sensitive composition. The risk of static electricity is often underestimated or even completely ignored by beginning amateurs in pyro, while it is actually one of the major causes of accidents in both commercial/industrial and amateur pyro setups.
- Wear proper protective clothing. A face shield, dust mask, heavy gloves and a leather apron are minimal. Wear cotton clothing. Hearing protection can be good but it also makes it harder to hear other people's warnings.
- Provide safety screens between you and compositions, especially when pressing, ramming, and sieving, or in other ways causing frictions/shocks/pressure etc.
- Be prepared for the worst. Have a plan for when something should go wrong. Have a fire extinguisher and plenty of water ready (excepting for mixtures for which water would create a greater hazard than ignition). Think beforehand of what might happen and how you could minimize the damage. Know how to treat burns. Inform someone else so he/she can help in case of an accident. Have a fast escape route from your working place.
- Work location: The work location for compounding of low-sensitivity propellant should be a minimum of 25 meters from any inhabited building, with distance to increase appropriately depending on the amount and type of material being used. All materials must be locked in proper storage facilities when not actually being used. Finished propellant/motors should be stored in a proper magazine.
- Neatness: Keep the area where propellant compounding is being carried out clean and neat at all times. Oxidizers, powdered metals, and other ignition hazards should be treated with appropriate care to minimize the danger of accidental ignition, with special care taken to avoid "dusting" of fine material. Never have more than one open container of chemical within your area at any time.
- Chemicals: Become familiar with the associated literature, including MSDS's for each chemical used. Don't use "makeshift" chemicals, but instead obtain technical-grade or appropriate/equivalent purity for propellant compounding. Learn about chemical incompatibilities and avoid them (examples: ammonium compounds with chlorate compounds; aluminum and any nitrate). Never make substitutions simply to see "if this works," but instead engineer mixtures to meet the pre-selected criteria.
- Training: The initial phases of your work should be performed under supervision of a knowledgeable person, one who has been properly trained in that which you are doing. Your initial work should involve mixtures that have been well characterized by others and have been found to be minimally sensitive. You should study regularly to learn more about the nature of your propellant and motor work. A good book about safety in pyrotechnics and rocket propellants is L. Edward Jones' Safety Manual for Experimental and Amateur Rocket Scientists.
- Amounts: Work with small amounts of materials. For well characterized minimally hazardous mixtures, make no more than can be used within a reasonable length of time. Uncharacterized experimental mixtures should be made initially in quantity not to exceed one gram, until the mixture has been properly characterized as to sensitivity and other hazard.
- Legal: Work in compliance with federal, state, and local laws. The local authorities having jurisdiction should be aware of your activities.
- Testing: Test the (impact and friction) sensitivity of mixtures using the smallest practical amounts of the mixture. Carefully note and avoid any mixtures that are unduly sensitive. Test any motor design at least three times, by proper static test, before committing that motor to flight.
- Motors: Rocket motors should be constructed of materials properly selected and engineered. Don't use makeshift materials. Each rocket motor should be designed so that its failure mode is longitudinal, and testing of such motors should be performed in a vertical mode until the propellant has been properly characterized. Strength of the casing material itself should be a minimum of 1.5 times the maximum expected stress.
- Waste: Dispose of scrap material and flammable waste from your operations properly, by remote ignition, on a daily basis or more often. Scrap and waste should not be allowed to accumulate.
- Carry out any other procedures needed to minimize properly the hazard to yourself, to others, and to your surroundings.
Some combinations of chemicals lead to especially sensitive or unstable mixtures. There are many more of such incompatible chemicals/mixtures than listed here, but these are some of the more commonly encountered types:
- Chlorates and sulfur:
Mixtures containing both are not only very sensitive to friction and shock but are also known to ignite spontaneously. The sulfur reacts with water and air to form trace amounts of sulfuric acid. This will react with chlorates to form chlorine dioxide, a yellow explosive gas that will ignite most flammable materials upon contact. Small amounts of barium or strontium carbonate are sometimes added to chlorate-based compositions to prevent buildup of acid, even in compositions without sulfur. Many older texts on pyrotechnics describe the use of chlorate/sulfur based compositions. Today, many alternative and much safer compositions are available, and there is therefore no excuse for the use of chlorate/sulfur mixtures. This also means chlorate-based compositions cannot be used in items that also contain sulfur-based mixtures. For example: chlorate-based stars cannot be primed with black powder. Nor can a H3 burst charge be used with black powder primed stars (or stars containing sulfur).
- Chlorates and ammonium compounds:
Mixing these will allow ammonium chlorate to form in a double decomposition reaction that takes place in solution (moisture speeds up the process). Ammonium chlorate is a highly unstable explosive compound. It decomposes over time, producing chlorine dioxide gas (see number 1). Mixtures are likely to spontaneously ignite upon storage or may explode for no apparent reason. An exception seems to be the use of ammonium chloride and potassium chlorate in some smoke compositions. According to Shimizu, this combination is safe due to the lower solubility of potassium chlorate (compared to ammonium perchlorate). It is for each individual to discern whether or not to still use these mixtures with great caution or to avoid them, as it seems inevitable that small amounts of ammonium chlorate will still form. The lower solubility of potassium chlorate will make it the main product in a double decomposition reaction, but not the only product.
- Chlorates with metals and nitrates:
These mixtures show the same problems as chlorate/ammonium compound mixtures. The reason is that nitrates can be reduced by most metals used in pyrotechnics to ammonium. The reaction rate of this reaction is increased by the presence of water. Over time (when drying, for example), these mixtures may spontaneously ignite or become extremely sensitive. The fact that ammonium forms in a relatively slow reaction is treacherous. These mixtures are referred to as 'death mixes' by some.
- Aluminum and nitrates:
Mixtures of these compounds sometimes spontaneously ignite, especially when moist. The mechanism is assumed to be as follows: the aluminum reduces some of the nitrate to ammonium, simultaneously forming hydroxyl ions. The aluminum then reacts with the alkaline products in a very exothermic reaction, leading to spontaneous heating up of the mixture. This can eventually lead to ignition. The reactions take place in solution and therefore moisture speeds up the reaction. The process is usually accompanied by the smell of ammonia. Some types of aluminum are more problematic than others. stearin-coated aluminum is generally safer to use. The whole process can be prevented in many cases by the addition of 1%-2% of boric acid. This will neutralize the alkaline products. It is best to bind such compositions with non-aqueous binder/solvent systems such as red gum/ethanol. Since aluminum/nitrate mixtures are extensively used, it is important to be aware of this problem, which is why the combination is listed here.