This employee wanted to test me. She learned real quick

I just had to fire someone today. I was so pissed off. So I have told my employees several times if a pan is hot place it on the table next to the dish pit because our dishwasher is deaf and he knows that table if for hot pans. Some of my employees continued to not do it and I've explained he has a disability. We have to make accommodations for him. He's safety is important. When he almost got burned because one of my employees was on her phone and places a hot pan with the regular dishes and one of my cooks stopped everything they were doing to grab his hand I said for now on if someone does that they're getting written up and if he gets hurt because someone did that they're getting fired. I had an issue with our supplies and was on the phone and already had a bitchy voice because I was annoyed and I hear my employees telling another one that the deaf dishwasher is here so she better put the hot dish on the hot dish table otherwise I'm gonna eat their ass and I hear one says "I don't care. The fuck". I walk out the storage and I say "Oh you don't care?" She just looked at me and moved her dish from the dish pit to the table and I said "No. You don't care, you can go not care somewhere else". I fired her right there. If you only care about someone's safety when I'm there to watch you, then I don't want you working here. She got pissed off and cussed me out and I said "I don't care". My employees know not to test me now and I was serious.