Dealing with my dad when hes in an extra foul mood?

He doesn't hit just yells a lot. My dad is a person who likes to get worked about anything and everything. I feel bad for not helping him, but I avoid as much as possible cause I never do it to his standards and I am out down and yelled at when I don't do it exactly as he wants. During these moods I avoid him, but many times I cannot avoid him. He'll go off on me for nothing and it makes tears spring to my eyes, I know I this shouldn't happen but it does. I never let him see the tears cause I know it will be worse. There's no way to talk to him cause he thinks he's perfect and can never make a mistake in life. How can I desensitize myself? This is unneeded stress and upset for no reason.