I don't believe the units are sealed in any way, other than a frame holding everything in place. LifePixel does use a "clean room" for replacing filters, as once dust gets in there, it's impossible to remove without disassembly of the entire thing.
FYI,
So Nikon will replace my sensor in about 5 days for exactly $471.52
It's not cheap so be very carful when you clean your sensor....
Still, I'm happy, I thought this is going to be more than a $1000........
G'Day to you all.