Helium is OK, but this gas that filled the Hindenburg isn't; no containers of it in your room
Ok, ok. [DOC] [TLE] DIY hydrogen generator - Instructables [PAR] Materials needed for this project:- Empty container with lid- Cables- Pencil- 
Luster ... potential energy in a gas cylinder but I have seen some memorable ... 
You brought up the issue of fuel first and I only sought to extend your bald .... 
That's because those balloon's are filled with Helium not Hydrogen.