Hazard Identification

DOE-HDBK-3010-94

Appendix B; Plutonium Recovery Facility

normally open only enough to maintain a small flow through the heat exchanger. A

temperature detector on the bath controls the position of the inlet valve to allow for

quick compensation of temperature fluctuations. The bath heating element is

controlled by a thermostat, but the bath temperature signal provides an alarm and

deenergizes the element if temperature exceeds 76 F. The pressure sensor on the

gaseous HF outlet line will also shut off the heater if pressure begins to rise

continuously.

A level sensor on the evaporator controls the position of the liquid HF inlet valve.

Nitrogen purge lines are provided on the system as well. They exhaust to the HF

storage tank scrubbing system. The final major feature of the evaporation system is

the installed rupture disc and relief valve. The rupture disc is designed to fail at 14

psig. The resultant pressurization of the piping between the rupture disc and the relief

valve will cause the installed pressure sensor to trigger an alarm locally, in the dry

line operating room and in the main control room. The sensor's signal will also cause

the liquid HF supply valve to the evaporator to shut.

The evaporator relief valve will lift at approximately 20 psig. The relief line will pass

through a single HEPA filter installed to preserve the integrity of the radiological

envelope within airlock areas. The line then passes through the ceiling of the room to

a roof vent elevated 15 feet above the actual roof of the building. This release will be

accompanied by an audible alarm on the roof triggered by the evaporator pressure

sensor. The limited flowrate needed to relieve pressure from the evaporator will not

create a significant personnel hazard due to the elevation of the roof vent.

The evaporator room itself is equipped with fluorine detectors, which are also in the

ventilation exhaust header. These units alarm in the same locations as the pressure

relief alarms.

2.3 H A Z A R D I DE N T I FI CA T I ON

This document presents in tabular form the hazards identified by the team evaluating the H-1

Plutonium Recovery Facility. It follows the process flow of the facility as it would occur,

and then identifies potential hazards in supporting activities in accordance with the building

layout. The two general types of hazards identified are as follows:

A-

Material of concern for release or a potential hazard in direct contact with a

material of concern.

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