Process Area - STD-1128-98master0317

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

areas should meet the criteria in ANSI N512-1974, Protective Coatings (Paints) for the

Nuclear Industry (ANSI, 1974b).

An emergency lighting system should be provided in radiation areas to facilitate egress in

emergencies. The emergency lighting should meet the requirements of the latest version of

NFPA 101 (NFPA, 1985).

C.4.3 Process Area

The plutonium process area is typically a group of contiguous rooms that contain all

operations involving plutonium, including processing, shipping, receiving, storage, and

waste-handling. To the maximum extent practicable, the facility design should provide

sufficient space and versatility to accommodate equipment for programmatic changes and

process modifications.

The initial line of defense to protect workers in a process area is the primary confinement

system, which includes enclosures, glove boxes, conveyor lines, the ventilation system, and

process piping. The primary confinement system should be designed to minimize the impact

of accidents and abnormal operations on people, facilities, and programs. The type of

confinement enclosure used (e.g., hood, glove box, remote operation cell) depends on the

amount and dispersibility of unsealed plutonium that will be handled and on the process

involved. Generally, if the quantity of unsealed plutonium exceeds 100 mg, the use of a

glove box should be considered. However, the applicability of this guideline will vary based

on the individual merits of each case.

C.4.3.1 Piping and Valves

Piping and valves for radioactive liquids should not be field-run (i.e., pipe and

valve locations should be located as specified on approved drawings and not at the

discretion of the installer).

Notches, cracks, crevices, and/or rough surfaces that might retain radioactive

materials should be avoided in the design of radioactive piping systems.

The piping system that collects contaminated liquids should be designed so that

effluent from leaks in the system can be collected without releasing the liquids into

personnel-access areas or to the environment.

When component or system redundancy is required, sufficient separation of

equipment should be employed so that redundant systems (or equipment) cannot

both be made nonfunctional by a single accident.

Stainless steel should be used in all radioactive waste and process system piping

and equipment to ensure that smooth, nonporous, corrosion-resistant materials are

in contact with contaminated liquids. For some applications, polyvinylidene

fluoride (PVDF) piping may be preferred for inside of confinement enclosures

because of its ease of fabrication, smoothness, nonporosity, and corrosion-

resistance. However, it undergoes severe degradation after about 7 x 107 rad of

exposure. In general, organic materials should not be used in process-piping

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