Cody,

The gas airs out within seconds of removing the rodent. It really isn't any concern. Very little actual CO2 is needed to euthanize the rodent in such a small container, it is really mostly used to displace oxygen very quickly. If you want an idea of how quickly the air dissipates, I can open the container and take a big wiff with no problem. And no, it's not just because I'm human: have you breathed straight CO2 before? It's not fun, trust me . Just a throwback to my curious paintball days.... :roll: