Controlled Area - STD-1128-98master0324

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

sometimes required. When using organics in the glove box, care must be exercised

in the selection of the material to minimize alpha radiation deterioration.

Fire protection should be provided in the glove box, enclosure, and conveyor

systems to meet DOE improved-risk objectives. Automatic fire suppression should

be provided in all new structures over 5000 square feet and in all structures having

a maximum possible fire loss (MPFL) in excess of $1 million or where the

maximum credible fire will result in the loss of use of a vital structure for a period

longer than that specified as acceptable by the applicable PSO [DOE Order 420.1a,

Facility Safety (DOE, 2002a)]. When the MPFL exceeds $50 million, a redundant

fire-protection system should be provided that, despite the failure of the primary

fire-protection system, will limit the loss to $50 million.

Discrete workstations within an enclosure should be separated from each other by

fire stops to prevent the spread of fire. Fire stops should be designed to be

normally closed. For systems in which fire stops must normally be open, closure

should be automatic upon actuation of the fire-sensing system. Instead of a

fire-sensing system, an oxygen-deficient atmosphere may be provided as the

normal or required operating atmosphere within the enclosure. Where automatic

fire-suppression systems are not required, a fire-detection system should be

installed. Provisions should also be made for manual fire suppression where it is

deemed necessary.

The actual sources inside the glove box should be shielded, if possible, instead of

shielding the glove box. However, the glove box should be equipped with or

capable of accepting any necessary neutron and/or gamma shielding.

C.4.4 Controlled Area

All support facilities that have a potential for periodic low-level contamination should be

located in the controlled area. These facilities include change rooms and decontamination

rooms for personnel; health physics laboratories; facilities for the receipt, temporary storage,

and shipment of radioactive and potentially contaminated materials; maintenance rooms for

regulated equipment; mechanical equipment rooms; and other laboratory facilities.

Air locks between controlled and uncontrolled areas should be used to provide confinement

of the controlled area if an inadvertent release of radioactive materials or a fire occurs. Air

locks should also be provided in controlled areas where there is a potential for radioactive

contamination to be spread from an area of high contamination to one of lower

contamination.

Where possible, each controlled area should have a single access and exit point for

personnel during normal operation. Access points should be accessible through change

rooms. Other access and exit points should be available as required for emergencies and in

compliance with the NFPA Life Safety Code (most current version) (NFPA, 1985).

Space for step-off pads and radiation monitoring and survey equipment should be provided

at the exit from controlled areas that are potentially contaminated and between high- and

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