I have this issue with H also. The other day when he was on a rant I said 'I understand your perspective' even though I completely disagreed. That wasn't good enough for him and he escalated a bit so I said 'I'm not going to allow you to yell at me' and walked away. This patter continued for a couple of days.
When he's calm I have better success with the "boundary" language. The hard part for me is something might trigger a rant that seems completely innocuous. I've learned to shut up and let the mood pass because trying to explain what I meant or clarify only gets more ranting.
He: WAH Me: LBW Precious: DD
~ I'm grateful for every day I have to improve the way I relate.