Helistudent, try this link for starters:
If you do get yourself into rotor wash induced whiteout due to blowing snow, you have few options. Either pull pitch and fly away on instruments, or land. In a simple, VFR helicopter, you might have only the latter option and the outcome might be as per this tragic accident.
To prevent arriving in the hover and generating your own whiteout, either don't fly in the first place (!),
plan to carry out a "zero speed", or run-on landing (aiming to keep the cloud of blowing snow behind you), or if you have HOGE power, an alternative is to carry out a high hover and blow the loose snow away before attempting a landing. The latter may not work so you may still have to go around and reconsider or abandon the landing altogether. If the whiteout is already there (e.g. fog/mist over lying snow, or someone else's blowing "snowcloud"), attempting a landing is extremely dangerous and should not be attempted. Go around and wait, or land somewhere else.