How do they know it is nerve gas this fast. It could be Fart in a Can...
That's dangerous stuff to mess around with:
Teen Bible Campers Hospitalized After Mixing Fart Spray and Deer Repellent in Prank (The Christian Post ^ | 07/26/2013 | Leonardo Blair)
1 - Guys get sick.
2 - Testing starts with the most threatening chemicals.
SOP in the security biz
They have monitoring equipment which will alert them. Doesnt tell them what kind but would tell them its an agent to be concerned with.
If it really is nerve gas they’d be dead so I’m skeptical.