Water Rocket - Safety

Safety

Water rockets employ considerable amounts of energy and can be dangerous if handled improperly or in cases of faulty construction or material failure. Certain safety procedures are observed by experienced water rocket enthusiasts:

• When a rocket is built, it is pressure tested. This is done by filling the rocket completely with water, and then pressurizing it to at least 50% higher than anticipated pressures. If the bottle ruptures, the amount of compressed air inside it (and thus the potential energy) will be very small, and the bottle will not explode.
• Using metal parts on the pressurized portion of the rocket is strongly discouraged because in the event of a rupture, they can become harmful projectiles. Metal parts can also short out power lines.
• While pressurizing and launching the rocket, bystanders are kept at a safe distance. Typically, mechanisms for releasing the rocket at a dstance (with a piece of string, for example) are used. This ensures that if the rocket veers off in an unexpected direction, it is less likely to hit the operator or bystanders.
• Water rockets should only be launched in large open areas, away from structures or other people, in order to prevent damage to property and people.
• As water rockets are capable of breaking bones upon impact, they should never be fired at people, property, or animals.
• Safety goggles or a face shield are typically used.
• A typical two-litre soda bottle can generally reach the pressure of 100 psi (690 kPa) safely, but preparations must be made for the eventuality that the bottle unexpectedly ruptures.
• Glue used to put together parts of water rockets must be suitable to use on plastics, or else the glue will chemically "eat" away the bottle, which may then fail catastrophically and can harm bystanders when the rocket is launched.