Azrael and his Lion Helm

[RastlinD]

Wanted to inquire about how this helm would work with the following rules interactions:

 

Unit inside a transport vehicle - My thought is that it only confers the save to his unit the vehicle is not part of the unit so thus no effect. 

 

Unit inside a building - Same as above correct?

 

Unit on battlements - This is my real concern how would this effect the building say for example a blast weapon scattered on top. Would the building then benefit from the save?

 

Thanks!

[Fibonacci]

"The Lion Helm confers a 4+ invulnerable save to Azrael and his unit."

 

So no, no and no.  He cannot join a vehicle in any of its forms so they are never part of his unit.