Are you kidding??! I've been working with NH3 and trying to stay upwind for about 35 years!  I do not and will not use it on my farm, though, so don't ever have a tank around. I use 28% liquid. A lot safer. 

I realize household ammonia is not the same as ag NH3 gas (thank goodness!), just asking if it might help keep out varmin. "Rats thrive in (liquid) ammonia stench"??  I doubt that. I'll report back results.