I’ve been around a small spill before..
You simply cannot breathe
We had a long training session when we worked near a 5” high pressure line that runs from NO to Ohio
Scary consequences if you hit one, but you won’t know it it for long
When I was in Water Treatment We used it combined with CL2 to make CLO2 for a longer lasting Disinfectant.
The fumes from CLO2 are toxic and that's why they tell you to not mix Household Ammonia and Bleach because they create the CLO2 gas. As if the 2 chemicals separate aren't toxic enough and sometimes people will mix them together anyway and use the mix in a confined space.
I was at a Training Class in Cleburne, TX and the Water Treatment Plant had a small leak in the valve on the NH3 Storage Tank and even being outside the smell was VERY noticeable even when 20-30' away from the Tank.