Containment states

Question 1

Describe containment state 1

Answer 1

The normal containment state which should be maintained at all times. The boundary of primary containment is to be complete and intact. All valves are to be shut or capable of being shut. Any open valve must be manned until shut. Secondary containment is to be available within 10 minutes.

Question 2

Describe containment state 1 (relaxed)

Answer 2

Containment state 1 can be relaxed to permit movement of equipment into and out of the RSC, provided the reactor is shutdown and in plant state H or below.

Question 3

Describe containment state 2

Answer 3

Equipment forming part of the primary containment structure may be removed for maintenance. Airlock doors may be opened to allow connection of repair services as long as they can be shut within 10 minutes.

Question 4

Describe containment state 3

Answer 4

Normal sea going state, when the sub is outside of coastal waters. The outer airlock doors can be defeated to ease passage through the RSC.

Question 5

Describe containment state 4

Answer 5

A relaxation of containment. Relaxation to this state requires approval from naval reactor plant authorisee (NRPA) normally used for a given repair.