As Brian mentioned in the Policy Integration thread,

Brian H wrote:
I believe Eric’s estimate is that it would take about 9 hrs. for the external housing/maintenance space to return to background levels after shut-off. So it would take about a day to turn around each annual or semi-annual servicing.

This design may be heating what would be known as the “hot side” of a fission plant’s heat exchanger. Not good. A search for Most Effective Neutron Shielding Materials produced this website: http://wardray-premise.com/structural/neutron.html which makes neutron and X-ray shielding products. Their Premadex product can be poured into molds at 95 to 100 degrees C, which could make it a candidate for the vacuum chamber’s material or the sleeve that the core would slide into in my design. In non-boiler applications, this would immensely reduce the mass and material requirements. I’m assuming that being non-ferrous, it would have no RF shielding abilities.

Elemental Composition

Element Percentage by Weight Concentration (Atoms cm-3)
Hydrogen 11.4 6.81 x 1022
Lithium[1] 1.3 0.11 x 1022
Oxygen 39.9 1.51 x 1022
Carbon 47.4 2.38 x 1022

So my questions are how thick this would have to be for a 1khz pulse rate (attenuating to background level), and will it absorb most of the X-rays heading in those directions in the process?