This warning is spot on. "Since it's odorless and colorless, you probably wouldn't even notice." — I remember being surprised reading a haz-card for liquid nit

This warning is spot on. "Since it's odorless and colorless, you probably wouldn't even notice." — I remember being surprised reading a haz-card for liquid nitrogen that said you could suffer serious brain damage from lack of oxygen before noticing anything odd. Humans feel we're suffocating when there's too much CO₂, not when there's too little oxygen.