This is a stupid question but are geiger counters safe on airplanes? I'm asking because i heard that geiger mullers might rupture due to the pressure diffrence, but i am not sure so i decided to ask here.
It is highly unlikely that a Geiger-Müller tube - be it made from glass or metal - will rupture at high altitude. Air planes at cruising altitude may have a slightly lower pressure than at ground level, but since the Geiger tubes tend to have lower pressure inside, the force on them would actually be greater at ground level!
The situation is different when using an Alpha-Particle sensitive detector, because they have a very thin membrane as window to allow Alpha to penetrate. But it probably would need a severe and quick pressure change - such as when oxygen masks fall out of the airplane headroom - to break the membrane. But even then chances are good that the membrane lasts.