For Sounding Balloons or Red Bull Stratos: Why not use hydrogen over helium

I am lovin' this "hydrogen hysteria"!

MUST show this thread to the guys that launch the radiosonde balloons at the weather bureau!

If you're not careful with black powder it can happen, mmm, fond memories of going to school with no eyebrows, eyelashes and frizzy hair!

Just so we know, CodingBadly, how did you loose your eyebrows with hydrogen?