The public space aspect is also a "you need to stand back this far"
Note the suit that the person is wearing in the Derezzed video - https://youtu.be/psoLXEBmfRg
Also note the grounding fences around the area.
The video with them and Tested gets into the tech of it - https://youtu.be/4m6EjnEYEEg
Small one... ok. Big one? Nope.