Working in an inert atmosphere Inert atmospheres (e.g., Ar, N2) are helpful in stabilizing reactive complexes and mediating sensitive reactions. Cylinder caps required when not in use Restraints required at all times Avoid riding elevators with cryogenic tanks Treat inert atmospheres with caution; humans cannot detect low oxygen levels, so leaks into the workplace can be dangerous. Below 11% O2, researchers may faint without warning. Exposure to deoxygenated atmosphere can cause death within minutes. Explicit safety requirements and good communication are required to prevent accidents.