Containment
The containment of IRIS is spherical and set to be approximately 22–27 meters across. This is compared to 58 meters high and 40 meters in diameter for a typical 600 MW PWR. Additionally, two thirds of the containment will be underground, giving it a lower profile, in addition to its already very small footprint. While the containment will be smaller than typical plants, it will also be rated for a higher maximum pressure, increasing costs.
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