Can you shield yourself from Unruh particles? In an old answer to a different question, Ron Maimon says yes:
You should think of the radiation as coming from the horizon--- if you place a refrigerated barrier between you and the horizon, you won't see any radiation past the barrier (at least not until it heats up). The reason is that the temperature of the barrier at the end furthest from the horizon forms the boundary condition for the Rindler Hamiltonian [...] and if it has a very long period in imaginary time, so does all the spacetime further along the Rindler x coordinate [...].
The barrier in his setup accelerates with you. What if it's inertial? For example, suppose there's a barrier suspended below you by a rope which you then cut. Does it instantly become transparent when it starts to fall toward the horizon? It seems that it must – it can't absorb the particles without continuing to heat up, and an inertially moving object in a vacuum can't heat up. But it's hard to believe that Unruh particles are similar enough to ordinary radiation that they seem to travel from the horizon to you, but different enough that they choose whether to interact with a solid object or completely ignore it based on the second derivative of its position.
Another possibility is that Ron Maimon is wrong and the particles don't travel from the horizon, but that seems no better. It would seem to imply, for instance, that if you're near a glowing black hole, you can't block the glow by closing your eyes, in stark contrast to ordinary blackbody radiation which seems to closely resemble Hawking radiation otherwise.
What really happens, and why isn't it as crazy as it looks?