Candidate reactor concepts—varying coolant, selected designs in brackets

Key requirements

Water-thermal (large EPR)

Sodium-fast

(PRISM)

Molten Salt-fast

(SaWB)

Helium-thermal

(HTR-PM)

Lead-fast

(BREST-OD-300)

Elimination of Reactivity Induced Accidents

4

2

1

5

2 - 3

Resistance to Loss of Active Core Cooling

- avoid exceeding critical temperatures

- avoid high fission product inventory

- provide sufficient heat storage & transfer capacity

1

1

1

4

2

n.a.

4¹

5

3

n.a.

5²

4

5

5

4¹

4

2 - 3

n.a.

4¹

5

Structural Integrity

- avoid high operating pressure [suitability of underground siting]

2

1 [2]

4

4³ [5]

4

5 [5]⁴

5

4 [5]⁴

4

4³ [4]

Use Non-chemically Reactive/Non-Toxic Materials

4

1⁵

2⁵ (non-stable)

5

4

Avoid Long-lived Radioisotopes

1

4

5

4

5

Enhance Proliferation Resistance

- avoid high enriched uranium

4

5

2

2⁶

2

2⁶

3

2 - 3

2

2⁶