I locked my dads for arm away. He’s arguing to get it back for self defense at his business. Please read details & answer ?

My father works at a business that honestly does need some kind of protection like pepper spray, taser, etc. I been there & a weapon is possibly useful for self defense. But he has left the gun loaded twice, he’s a drunk also so I don’t trust him. My brother & mom don’t either but he creates huge arguments & I know he’s going to make one if I say no again. My mom is telling me to just give it to him and make him keep it at work. But I don’t trust him, I have told him several times to keep it locked but he doesn’t. It has gone off once in the house before too When he was unloading it but he claims “ it’s ok” bc he had it pointed down