It's Never a Good Idea to Mix Bleach and Ammonia
Chlorine gas is released when ammonia and bleach are mixed together. It is such a powerful toxin, chlorine gas was used as a chemical warfare agent in World War II.
With all the cleaning agents that contain either bleach or ammonia, exposure to chlorine gas is quite common. It's important to know what to do if you accidently mix bleach and ammonia.
From Anne Marie Helmenstine, Ph.D., your Guide to Chemistry:
Some of the common chemicals found in your home shouldn't be mixed together. It's one thing to say "don't mix bleach with ammonia", but it's not always easy to know what products contain these two chemicals.Common Household Chemicals (About Chemistry)


Comments
This cleaning tip website recommends mixing bleach and ammonia to clean garbage cans. Do you think it is safe if it is outdoors?
Absolutely NOT! There is no good time to mix bleach and ammonia. As you stick your head in the garbage can to clean it, you’re going to become overwhelmed and die. Not good.
Good warning Rob! I had a girlfriend that mixed bleach and amonia – and ended up with fried lungs in the ER.
My cat peed on a white cushion this morning but I was on my way to work. In a rush I just poured bleach on it and covered it with a plastic sheet, then went out to work. I didn’t know about bleach/ammonia. The room is closed off so that cat can’t get in there, but is the mixture going to turn into a poison cloud now? I’m suddenly very worried
It’s never safe to leave any animal in a closed room with either open bleach or ammonia. Mixing the two is of course worse. But after all.. it is just a cat. Don’t worry about it!