This is not the way to avoid damage from Flame Wall or Lava Strike, it's to avoid lava fluid on the floor which can you swim in it around Sartharion.
It's easy to do, just jump into the lava and then do anything that would make you immune. Like using Ice Block, Divine Shield of have a paladin use Divine Intervention.
Remove the buff while you're still in lava and you'll never take damage from lava you're in anymore as long as you're not moving out from it and go in again. ( Jump out also remove this bug, so don't jump. )
I use this for my achievement, Gonna Go When the Volcano Blows because when you're in lava, chance to get Lava Strike ( Not the Flame Wall ) is nearly to none.
Searched and found another post to avoid lava damage by keep jumping
http://www.mmowned.com/forums/wow-ex...va-damage.html
I don't know why tank would need to avoid lava damage, but if you do, you could also try this![]()