1. The starboard exhaust fan and filter system is in operation with the other in standby
status. The port filter system is not used except under emergency conditions; the one
exception being the purging operation. However it must be tested once weekly.
2. The supply valve RS-40V is throttled to admit approximately 800 cfm into the upper
3. Ventilation of the control rod electrical and hydraulic cubicles is in service
4. A negative pressure of 0.3" wg is being maintained in the reactor compartment.
5. The ventilating systems servicing the laboratory spaces in the forward end of the
reactor compartment are in operation. (Fans 2-99-1 and 1-102-2)
6. The decontamination shower duct is closed.
7. Pressure differential across the filters is maintained at less than:
a. Prefilter - 0.8 inches wg.
b. Absolute Filter - 4.0 inches wg.
c. Charcoal Filter - 3.4 inches wg.
8. A standard DOP (dioctyl-phthalate) test shall be performed at intervals not to exceed
ninety (90) days, and following each filter change or inspection. This is to determine that
the aerosol filtration efficiency remains adequate.
9. Following each change or inspection of an iodine absorbing filter, or at intervals
not to exceed ninety (90) days, a test shall be performed to determine the iodine removal
efficiency of these filters.
10 At intervals not to exceed ninety (90) days, the reactor compartment exhaust filter
housings, which are exposed to the reactor compartment, shall be demonstrated to be
leaktight by soap bubble testing.
11. The ambient temperature in the upper reactor compartment is being maintained at less
than 115F. The recirculation system may or may not be in operation.
12. The sample system hood and waste gas manifold shall be open to ventilation
B. Minimum Condition for Reactor Operation
1. Negative pressure is maintained within the reactor compartment.
2. The reactor compartment must be maintained at 120F or less.
3. If these conditions cannot be met, the reactor must be shut down and cooled down to
a point below 200F.
C. Emergency Operation
1. IF an emergency condition arises, e.g., a suspected MCA, filter breakthrough, etc.,
the port filter system mist be placed into operation immediately.
[MCA is Maximum Credible Accident.]
2. MBT B-110-2 must be switched manually to the Emergency Board for continued operation
upon loss of the main SWB.
My text copyright 2020 Tommy Johnson, all rights reserved. I believe the Savannah documentation is property of
MARAD or the US government.