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Data Center Design and Operations

Tier II

Tier II adds redundant capacity components but still generally requires shutdowns for some maintenance and has distribution-path exposure. It is a step up from basic capacity but not concurrently maintainable.

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RDHx

Rear Door Heat Exchanger is a heat exchanger mounted on the exhaust side of a rack to remove heat before it enters the room. It can help densify air-cooled or hybrid deployments without fully converting to direct liquid cooling.

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Liquid cooling

Liquid cooling removes heat using liquid closer to the IT components than traditional room air cooling. It is increasingly important for AI workloads because rack power densities can exceed practical air-cooling limits.

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Seismic risk

Seismic risk is earthquake-related hazard and vulnerability for a site. It affects structural design, equipment anchoring, uptime planning, insurance, and regional resilience assumptions.

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