Safety Grades 6–8
Safety for the middle-school track (grades 6–8)
Read this page before Lesson 1, and again before launch day (Lesson 9).
The big rules
- Motors are 12+, and only adults handle them. Model rocket motors and Rocket Builder kits are rated 12+. An adult buys, stores and prepares every motor, puts in the igniter, puts the rocket on the pad, connects the clips, holds the safety key and presses the launch button. Students design, build, check, count down, track and record. Students never carry the launch key. Students under 12 (some 6th graders) do every lesson but take launch-day jobs away from the pad.
- Glasses on for straw, stomp and fizzy rockets and at the pad, for everyone nearby.
- Never aim any rocket at a person, animal or window.
Classroom activities
- Straw and stomp rockets: glasses on; aim up or along an empty space; wait until everyone is behind the launcher.
- Fizzy film-canister demo (optional): adult-led only. The adult keeps the tablets (Alka-Seltzer contains aspirin). Outside, glasses on, never lean over a canister. If one doesn't pop, wait at least 30 seconds; the adult picks it up pointing away from faces.
- Swing test: outdoors, nobody within 3 m, a string about 1 m long. It's a demonstration only.
- Parachute drops from a height: an adult does the dropping.
- Inclinometer: never look at the sun through the straw.
- 3D printer: the nozzle and bed are hot. An adult runs the printer, in a room with fresh air. Adults handle the glue.
The NAR Model Rocket Safety Code (a plain summary)
The National Association of Rocketry's code is what every launch in this unit follows. Read the official code at nar.org before launch day.
- Materials. Light materials such as paper, wood, rubber and plastic. No metal for the nose, body or fins. (Printed PLA is fine.)
- Motors. Only certified, store-bought model rocket motors, used exactly as the maker says. Never change, open or reload one. Store them away from heat and flames.
- Ignition. An electrical launch system with electric igniters. The controller has a safety key, and its button springs back to "off".
- Misfires. If it doesn't launch, take out the safety key (or disconnect the battery) and wait 60 seconds before anyone walks up.
- Launch safety. Count down out loud from 5. Everyone pays attention and stands at least 15 feet (about 5 m) away for D motors or smaller, 30 feet for bigger ones. Check the rocket is stable before its first flight.
- Launcher. A rod or rail within 30 degrees of straight up, with a blast deflector. Clear dry grass and anything that burns from around the pad. Keep the rod top above eye level or covered.
- Size. No more than 1,500 g at liftoff. (All the rockets in this unit are far smaller.)
- Flight safety. Never launch at targets, into clouds, near airplanes or over people.
- Launch site. Outdoors, in a large open area away from tall trees, power lines and buildings. Not in winds over 20 mph. The field must be at least as big as the table below.
- Recovery. A parachute or streamer, with flame-resistant wadding.
- Recovery safety. Never try to get a rocket out of a power line, a tall tree or another dangerous place. Never try to catch a rocket.
Minimum field size (from the NAR code; also used by Rocket Builder):
| Motor class | Total impulse (N·s) | Smallest field side |
|---|---|---|
| 1/4A, 1/2A | up to 1.25 | 50 ft (15 m) |
| A | 1.26–2.5 | 100 ft (30 m) |
| B | 2.51–5 | 200 ft (60 m) |
| C | 5.01–10 | 400 ft (120 m) |
| D | 10.01–20 | 500 ft (150 m) |
| E, F | 20.01–80 | 1,000 ft (300 m) |
This is the smallest field. A rocket drifts under its parachute, so Rocket Builder often suggests a longer one (Lesson 7 shows how to work it out).
Also check local rules (towns, parks and school districts may have their own), fire danger and burn bans, and stay well away from airports.
Launch day rules
- Adults only: motors, igniters, the launch key, loading the pad and clipping the wires.
- Safety glasses at the pad; everyone at least 15 feet back when a rocket is armed (30 feet for motors bigger than D); a class stays farther back behind a marked spectator line.
- Wind under 20 mph. No launching near trees, power lines, buildings, roads or people who aren't part of the launch.
- Count down out loud from 5. Everyone watches the rocket until it's on the ground.
- Misfire: the adult takes out the key and everyone waits 60 seconds before going to the pad.
- The recovery crew goes only when the adult in charge says so. Never catch a rocket.
- After the flight the motor casing is hot. An adult takes it out once it cools.