Definitions cont'd - hdbk11290116

DOE-HDBK-1129-99

4. An area having structures or systems from which releases of hazardous materials are

controlled. Primary confinement systems are process enclosures (gloveboxes, conveyors,

transfer boxes, and other spaces normally containing hazardous materials). Secondary

confinement areas surround one or more primary confinement systems (operating area

compartments). (DOE O 435.1)

Containment system

1. Any equipment, structure, or systems that serve as an integral and essentially leak tight

barrier against the uncontrolled release of hazardous/radioactive material to the environment

and other areas within the facility. Examples include process piping, sealed containers,

tanks, gloveboxes, and any other closed loop system, which holds the material for possible

recovery of tritium. (U.S. DOE Tritium Focus Group)

2. A collection of passive barriers that can satisfy a specified leak criterion without operation of

any ancillary equipment. An example of a containment system is a series of piping and

vessels enclosing tritium gas operations. (DOE-HDBK-1129-99)

3. A structurally closed barrier and its associated systems (including ventilation) between areas

containing hazardous materials and the environment or other areas in the nuclear facility

that are normally expected to have levels of hazardous materials lower than allowable

concentration limits. A containment barrier is designed to remain closed and intact during all

design basis accidents. (DOE O 435.1)

Derived Air Concentration (DAC) For the radionuclides listed in Appendix A of 10 CFR 835,

the airborne concentration that equals the Annual Limit of Intake (ALI) divided by the volume of

air breathed by an average worker for a working year of 2,000 hours (assuming a breathing

volume of 2400 m3). (DOE 10 CFR 835)

Derived Concentration Guide (DCG) The concentration of a radio nuclide in air or water

that, under conditions of continuous exposure for one year by one exposure mode (i.e.,

ingestion of water, submersion in air, or inhalation), would result in an effective dose equivalent

of 100 mrem (1 mSv). DCGs do not consider decay products when the parent radionuclide is

the cause of the exposure. (DOE 5400.5)

DOE/DOT Type A, approved shipping package For the purpose of this text, these are

packages that can be used for the transport of Type A quantities of radioactive materials. The

two typical packages used for solids are metal 55-gallon drums with full removable lids and

metal boxes 4 feet wide by 4 feet high and 7 feet long with removable lids. DOT 7A packages

may be fabricated in almost any size to fit special needs like packaging of gloveboxes.

Facility segmentation The concept of independent facility segments should be applied where

facility features preclude bringing material together or causing harmful interaction from a

common severe phenomenon. Therefore, the standard permits the concept of facility

segmentation provided the hazardous material in one segment could not interact with

hazardous materials in other segments. For example, independence of HVAC and piping must

exist in order to demonstrate independence for facility segmentation purposes. This

independence must be demonstrated and places the "burden of proof" on the analyst.

Additionally, material contained in DOT Type B shipping containers (with or without overpack)

may also be excluded from summation of a facility's radioactive inventory if the Certificates of

Compliance are kept current and the materials stored are authorized by the Certificate.

However, Type B containers without overpack should have heat protection provided by the

facility's fire suppression system. (DOE-STD-1027-92, Rev. 1)

B-2