I have done three HAB launches, all using helium and have a fourth one coming up.. After that, I will be launching a balloon with another scout troop and they cannot afford helium and we have to use hydrogen. I know that hydrogen launches can be done safely with the right equipment and procedures. Does anyone know exactly what a hydrogen launch entails?? Please reply back ASAP. Really hoping for a successful flight. Of course, I have done Googling, but haven't found adequate information on this yet.