Is the voltage across a turned off transistor a problem?
But when it's turned OFF the Collector wil be at 48V and the Emitter at 0V.


Is 48 V more than 30 V? Yes, then you have a problem.

The off state is exactly the state that's normally expected to cause the highest \$V_{ce}\$ and where the maximum \$V_{ce}\$ spec is most likely to become important.