Wiki reference for the question. EXPLODE LEVEL 1 AUTOMATIC SKILL Obligatory. REQUIREMENTS The user must be in the Unconscious state for this Special Skill to activate. EFFECTS This Special Skill forces its user to detonate automatically when he enters in the Unconscious state. At the end of the Order in which the user entered the Unconscious state, place a Circular Template centered on the user's base. This Circular Template indicates the Area of Effect of the explosion. Explode causes Damage 13 hits with Shock Special Ammunition. Once all Rolls have been made, the user enters in Dead state and it is removed from the game table. REMEMBER If the user enters the Dead state directly due to a Special Skill (such as V: Dogged), a Special Ammunition (such as Shock) or because he suffered the loss of more Wounds than his current Attribute during a single Order, then he does not Explode. REMEMBER If a unit's Troop Profile indicates only "Explode", consider that unit to have Level 1 of this Special Skill. Will Explode L1 trigger if friendly models are in the AOE? If so will it cause them to take an armor save? I'm not reading anywhere in this rules that friendly units will not allow this ability to trigger.
Correct, Explode 1 is pretty much the only thing that can cause friendly fire in the game. The only thing that will cancel it is a Civilian (or using Dogged/Biolocator instead on a Kuang Shi)
And, more importantly, until they redid the Civilian rules in HSN3, it used to be possible to lose the game by exploding next to your own HVT.
Which you are forced to use if it would affect your own troop, (the civilian neuters the AOE, I think, so acts as human shield XD). atm I think only the Morat "zergs" can affect friendlies when exploding (because they have no way to avoid doing so).