General Design Considerations - STD-1128-98master0310

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

C.2.1 General Design Considerations

It is DOE's policy to design, construct and operate its facilities such that the exposure of

employees and the public to hazardous materials is maintained ALARA. Detailed guidance

for implementing ALARA and the application of the optimization process to facility design

is provided in PNL-6577, Health Physics Manual of Good Practices for Reducing Radiation

Exposure to Levels That Are As Low As Reasonably Achievable (Munson et al., 1988).

Additional guidance is provided in ICRP Publication 55, Optimization and Decision Making

in Radiological Protection (ICRP, 1989), and CONF-920468, Proceedings of the

Department of Energy ALARA Workshop (Dionne and Baum, 1992).

Equipment reliability and human-factors engineering should be considered in the design of

plutonium facilities. Both of these factors may significantly affect radiation doses and the

effectiveness of personnel response to abnormal conditions. Reliability data may be

available for much of the equipment that will be used. If industry information is not

available, reliability analyses should be conducted. The degree of reliability that is justified

may require an evaluation of the cost of the reliability versus the expected dose reduction.

The equipment should be designed such that the failure of a single component does not

result in the loss of capability of a safety class system to accomplish its required safety

function. Analyses of hazards and assessments of risks should be made during conceptual

and preliminary design activities and further developed during the detailed design phase.

The safety analyses should be performed in accordance with 10 CFR 830, Nuclear Safety

Management (DOE, 2001e).

In the planning and designing of buildings, other structures, and their operating components

and systems, all aspects of operation and maintenance should be considered. This includes

accessibility, dismantling, replacement, repair, frequency of preventive maintenance,

inspection requirements, personnel safety, and daily operations. Facility planning and

design should use the knowledge and experience of those persons who will be responsible

for operating and maintaining the completed facility. The "lessons learned" from the

operation and maintenance of existing facilities should be used to avoid repeating mistakes

made in past designs.

If possible, equipment that requires periodic inspection, maintenance, and testing should be

located in the areas that have the lowest possible radiation and contamination levels. For

equipment that is expected to be contaminated during operation, provisions should be made

for both in-place maintenance and for removal to an area of low dose rate for repair.

Maintenance areas for repair of contaminated equipment should include provisions for

containment or confinement of radioactive materials.

Engineered safety and control systems should be designed so that they continue to function

during and following an accident or emergency condition. The need for emergency systems

and facilities should be determined and incorporated in the facility design. Facilities should

be designed to facilitate the arrival and entry of emergency personnel and equipment in the

event of a radiological emergency and to allow for access by repair/corrective action teams.

Equipment should be available to allow for an early and reliable determination of the

seriousness of an accident or abnormal event. Depending upon the consequence of potential

accidents, consideration should be given to relaying all such equipment alarms to a central

control system or a continuously manned area. Installed on-line equipment should be

protected to the extent necessary to ensure its reliability under accident conditions. To

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