Answered Warning for T trap

This is regarding how much warning you should give for a T trap. Specifically the map seriouscraft (something) not sure whole name but the one with the t trap where tnt comes in the middle.
In this map there is a warning for the t trap as it gives them 8 seconds to run from it. Is this enough warning for the trap or would you have to say like middle in t chat

Thanks

 

Hey, you need to give a warning over voice or chat about this as not everyone will check the top right of the screen, as seen in the five second grace period rule we have.

 

What would be seen as warning like t trap or middle?

 

Something to the extent of "I'm using the TNT trap in the middle of the map" is sufficient.