So, contradicting statements here. Tohaa gets hit by fire ammo. Uses a symbiomate to ignore the damage and move on. Is he Burnt or not? Symbiomate states: "if its user, the trooper who the SymbioMate has been assigned to, is in the Active Symbiont Armor state and receives a successful Attack and declares the use of his SymbioMate, he will not perform an ARM/BTS or the correspondent roll, and the Damage and effects of the Special Ammunition or Attack will be ignored." Burnt states: "Troopers with Special Skills or pieces of Equipment with the Fire-Sensitive Trait enter this state by receiving a hit from a weapon using Fire Special Ammunition, regardless of the result of their ARM Roll."
I think the part of the line "and effects of the Special Ammunition or Attack will be ignored" (emphasis added) is relevant here. Becoming Burnt is an effect of Fire ammo.
I have a related question and since the Forum rules seem to be fine with thread necromancy, here I go. My question is a bit more basic and I think I already know the answer, I just want to check the technicalities with you guys. Situation: A model with Symbiont Armor in Active Symbiont Armor state is hit by Fire Ammo, but makes its armor save. The model has no other fire-sensitive equipment or special skills. My interpretation: The Rules for Fire Ammo state that a model with fire-sensitive equiment enters the burnt state if hit with fire ammo (1). The burnt state states that any equipment that refereces being disabled by being burnt is disabled (2). However, Symbiont Armor states that the Active Symbiont Armor state is only lost on a failed ARM/BTS save (3). My conclusion: The model enters the burnt state, but it doesn't actually do anything. Any thoughts? (1) http://infinitythewiki.com/en/Fire_Special_Ammunition : Additionally, a trooper affected by Fire Special Ammunition who has Fire-Sensitive Special Skills or Equipment will enter the Burnt state, regardless of the result of the ARM Roll. (2) http://infinitythewiki.com/en/Burnt : Similarly, Fire Special Ammunition disables all Levels of the Impersonation Special Skill and all Levels of ODD, Holoprojector (see Infinity Human Sphere) and any other pieces of Equipment or Special Skills that indicate so in their description, even if the affected trooper passed his ARM Roll. (3) http://infinitythewiki.com/en/Active_Symbiont_Armor : In this state, failing an ARM Roll caused by Fire Special Ammunition means losing all the points of the Wounds/STR Attribute of the Active Symbiont Armor Troop Profile. If the bearer loses more points of his Wounds/STR Attribute during that Order, deduct them from the Inactive Symbiont Armor Profile.
Each Fire-sensitive item says what happens to it in Burnt state, unless already stated in the state. So you're right, there is no additional effect.