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INITIAL SAFETY CODE FOR EXPERIMENTAL SOLID-PROPELLANT PREPARATION AND MOTOR CONSTRUCTION

1. Overall safety: Actions need have safety foremost in mind. Don't become complacent, always be prepared for an accident. Recognize that a mixture can ignite at any time, prepare accordingly. Remember Murphy's Law: "Anything that can go wrong will".

2. Work location: Your work location for compounding low-sensitivity propellant should be a minimum of 75 feet from any inhabited building, distance to increase appropriately depending on the amount and type of material being used. Specially designed testing facilities may be used in University, Professional Laboratories or other places when appropriate. All materials needs to be locked in proper storage facilities when not actually being used. Finished propellant/motors should be stored in a proper magazine and used as soon as practical.

3. Neatness: You need to keep areas 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. Special care needs to be taken to avoid "dusting" of fine material. It is strongly recommended that you not have more than one open container of chemical within this area at any time.

4. Chemicals: Become familiar with the associated literature, including MSDS's for each chemical used. It is strongly recommended that you not use "makeshift" chemicals, you should instead obtain technical-grade or appropriate/equivalent purity for propellant compounding. You need to learn about chemical incompatibilities and avoid them (examples: ammonium compounds with chlorate compounds; aluminum and any nitrate). It is strongly recommended that you do not make substitutions simply to see "if this works," but instead engineer mixtures to meet the preselected criteria.

5. Training: The initial phases of experimentation need to be performed under supervision of a knowledgeable person, who has been properly trained in that which you are doing. Your initial work should only involve mixtures that have been well-characterized by others and have found to be minimally sensitive. Regular study to learn more about the nature of propellant and motor work is very important to your safety.

6. Amounts: Work with small amounts of materials. For well-characterized minimal-hazard mixtures, you should 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 characterised as to detonation, ignition sensitivity and other hazard.

7. Safety equipment: It is strongly recommended you use proper safety equipment, including eye protection, blast shields, respirator, and flame-resistant clothing at all times. A water-type fire extinguisher of appropriate size should always be at hand, except for mixtures which water would create a greater hazard than ignition.

8. Legal: All rocketry experimenters need to work in compliance with federal, state, and local laws. The local authorities having jurisdiction need to be aware of your activities.

9. Testing: You need to test the (impact and friction) sensitivity of mixtures using the smallest practical amounts of the mixture. You should carefully note and avoid mixtures that are unduly sensitive. Any motor design needs to be properly static tested at least three times before committing that motor to flight. Burn rates need to be tested for each new propellant combination prior to using it in a motor.

10. Motors: Rocket motors need be constructed of materials properly selected and engineered. It is strongly recommended that you do not 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 needs to be a minimum of 1.5 times the maximum expected stress.

11. Waste: It is highly recommended that you dispose of scrap material and flammable waste from my operations properly, by remote ignition, on a daily basis or as soon as possible. Scrap and waste will not be allowed to accumulate, this becomes a significant flammability hazard.

12. You may need to carry out additional procedures to properly minimize the hazard to yourself, others, and your surroundings. Be observant and aware of your safety needs

RCS has MSDS for several popular propellant chemicals posted on their website. Emedco has a searchable database of over 200,000 chemicals. Reading the MSDS and understanding the chemicals you use can save you much grief.