Responsibilities of Health Physics Staff

DOE-STD-1128-98

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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