BD offers a product called the Turbo Guard. It's really overpriced...but a bolt-on affair.
Mildly modified Cummins B5.9's frequently see 50psi+...going from that much boost back to idle is a really nasty transition that places the bearings in the turbo in an unfair sitation. Over time, these bearings will wear out prematurely. By relieving the pressure seen when the soot pedal is lifted and the engine is returning back to idle, your turbo will live longer - maybe.
I've seen a few kits out there and they do work as advertised. The need for these is real for those making frequent trips between 0 and 50psi...like with a manual transmission between gears.
Cheers,
Matt