Responsibilities pf Health Physics Staff

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

7.4.2.3 Biological Indicators

Earlier in this section, a quick-sort method was described using neutron activation of

sodium in the blood as an indicator of worker exposure. More sophisticated

laboratory analysis of blood samples can be performed to obtain a more accurate

estimate of worker dose, as discussed in Delafield (1988) and Hankins (1979). The

use of neutron activation of sulfur in hair (32S(n, p)32P) is another method to estimate

absorbed dose for workers involved in a criticality accident (Petersen and Langham,

1966). The orientation of the subject can also be determined by taking samples of hair

from the front and back of the person. Hankins (1979) described a technique for

determining neutron dose to within 20-30% using a combination of blood and hair

activations. Their evaluation was independent of the worker's orientation, of shielding

provided by wall and equipment, and of neutron leakage spectra.

7.5

RESPONSIBILITIES OF HEALTH PHYSICS STAFF

The health physics staff should have a basic understanding of program structure, engineering

criteria, and administrative controls as related to nuclear criticality safety as reviewed in earlier

sections of this chapter. Additionally, the health physicist's responsibilities include emergency

instrumentation and emergency response actions.

7.5.1 Routine Operations

During routine operations the health physics staff's responsibilities related to nuclear

criticality safety include calibrating, repairing, and maintaining the neutron criticality alarm

detectors and nuclear accident dosimeters, and maintaining appropriate records. The health

physics staff should be knowledgeable of criticality alarm systems, including alarm design

parameters, types of detectors, detector area coverage, alarm set-points, and basic control

design. The staff should also be familiar with plans for emergency response.

The health physics staff should maintain an adequate monitoring capability for a nuclear

criticality accident. In addition to the criticality alarm systems and the fixed nuclear

accident dosimeters discussed above, remotely operated high-range gamma instruments,

personal alarming dosimeters for engineering response/rescue teams, neutron-monitoring

instrumentation (in case of a sustained low-power critical reaction), and an air-sampling

capability for fission gases should be maintained.

Other support activities may include assisting the nuclear criticality safety engineer or

operations staff in performing radiation surveys to identify residual fissionable materials

remaining in process system or ventilation ducts.

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