[bjoli]

On a related note: A friend of mine was exposed to high co2 levels while on a freight ship. He says it is the absolute worst feeling he has ever felt, with panic and convulsions and vomiting. He survived because a colleague of his managed to get him out.

Kinda makes me wonder why it is still allowed in animal slaughter. It is cheap and gets the job done, but there must be better gasses. There are loads that just makes humans pass out, and it must be the same for animals.

[dredmorbius]

That sounds like it might have been carbon monoxide poisoning.

https://www.mayoclinic.org/diseases-conditions/carbon-monoxi...

Though symptoms are quite similar to those of CO2 poisoning:

https://www.emedicinehealth.com/wilderness_carbon_dioxide_to...

One of the symptoms of CO poisoning I've heard mentioned is of a sense of doom or dread.

[bjoli]

Nope, that was co2. It is similar to CO, but in animals at least it gives a more aversive reaction.