Cryogenic Vault Inner Shield
Multi-Layer Tungsten/BPE Shield Around CRY Samples
The Cryogenic Vault Inner Shield is a 2,000-kilogram protective barrier comprising 20 millimeters of tungsten alloy, 100 millimeters of boronated polyethylene, and a 316L stainless steel inner liner. Sited within subsurface repositories in the Lunar Ark system, it isolates cryopreserved biological samples from ambient lunar radiation, which reaches 200 to 380 mSv per year unshielded. To protect sensitive payloads against cumulative exposure across a 100-year operational lifetime, the layered tungsten and boronated polyethylene attenuate gamma radiation and neutrons, maintaining internal doses below 1 mSv per year at zero power consumption.
Multi-layer tungsten + boronated PE shield around cryogenic biological sample vault providing maximum dose reduction for the most critical preservation payload.
Purpose
Multi-layer tungsten + boronated PE shield around cryogenic biological sample vault providing maximum dose reduction for the most critical preservation payload.
Context
Child of L2-RAD-SPOT within the Lunar Ark system
Principles
- ▸Maximum shielding effort focused on biological cryo vault
- ▸Layered tungsten (gamma) + BPE (neutron) configuration
- ▸Sample dose target <1 mSv/year (vs ~200-380 mSv/yr unshielded)
- ▸Internal access via radiation-sealed lock
- ▸Periodic dosimetry verifies effectiveness
Typical implementations
- ▸NASA biological sample shielding studies
- ▸Earth-based long-term seed vault shielding (Svalbard)
- ▸Nuclear medicine shielding (terrestrial)
Lunar considerations
- ▸Biological samples most sensitive — design for worst-case 100-yr cumulative dose
- ▸Heavy shielding adds mass but is justified for preservation mission
- ▸Combined with sub-surface siting for additional shielding
Specifications
Functional
| primary function | Multi-layer tungsten + boronated PE shield around cryogenic biological sample vault providing maximum dose reduction for the most critical preservation payload. |
| tungsten thickness mm | 20 |
| bpe thickness mm | 100 |
| internal dose msv per yr target | 1 |
Physical
| mass kg | 2000 |
| materials | Tungsten alloy, Boronated PE (B4C-HDPE), 316L SS inner liner |
| vacuum compatibility | True |
Operational
| power consumption w | 0 |
| thermal range c | -40, 70 |
| lifetime years | 100 |
| mtbf hours | 1000000 |
Interfaces
Provides
- Inner vault wall <1 mSv/yr
Requires
- Vault structural support
- Dosimetry monitoring feedback
Cite this entry
Lunar Ark Codex. "Cryogenic Vault Inner Shield" (L3-RAD-SPOT-CRY). Retrieved 10 September 2026, from https://lunarark.com/entry/L3-RAD-SPOT-CRY
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.