Let´s say a pokemon with 40 or less base HP holding a Focus Sash battling against another pokemon that uses Dragon Rage. Will the Focus Sash user faint because Dragon Rage always take 40 HP or will it survive because of the Focus Sash?
The person with the Focus Sash will survive as long as they are at full HP when dragon rage is used against them.
Source-Experience
Nope. The Focus Sash will work. http://bulbapedia.bulbagarden.net/wiki/Focus_Sash#Focus_Sash
If the holder has full HP and is hit by an attack that would otherwise cause fainting, it can survive with 1 HP. Can also protect against multi-hit moves, recoil damage, and self-inflicted confusion damage, but not from Future Sight or Doom Desire. Disappears after use.
