Standard Guide for Design of Equipment for Processing Nuclear and Radioactive Materials
|Publication Date:||10 June 2000|
This guide covers equipment used in shielded cell or canyon facilities for the processing of nuclear and radioactive materials. It is the intent of this guide to set down the conditions and practices that have been found necessary to ensure against or to minimize the failures and outages of equipment used under the subject circumstances.
It is intended that this guide record the principles and caveats that experience has shown to be essential to the design, fabrication, and installation of equipment capable of meeting the stringent demands of operating, dependably and safely, in a nuclear processing environment that operators can neither see nor reach directly.
This guide sets forth generalized criteria and guidelines for the design, fabrication, and installation of equipment used in this service. This service includes the processing of radioactive wastes. Equipment is placed behind radiation shield walls and cannot be directly accessed by the operators or by maintenance personnel because of the radiation exposure hazards. In the type of shielded cell or canyon facility of interest to users of this guide, either the background radiation level remains high at all times or it is impractical to remove the process sources of radiation to facilitate in situ repairs or carry out maintenance procedures on equipment. The equipment is operated remotely, either with or without visual access to the equipment.
This guide is intended to be applicable to equipment used under one or more of the following conditions:
The materials handled or processed constitute a significant radiation hazard to man or to the environment.
The equipment will generally be used over a longterm life cycle (for example, in excess of two years), but equipment intended for use over a shorter life cycle is not excluded.
The material handled or processed must be retained, contained, and confined within known bounds for reasons of accountability or to minimize the spread of radioactive contamination.
The materials handled or processed must be kept and maintained within one or more of the following conditions:
(1) In a specific geometric array or configuration, and
(2) Within a range of conditions that have been determined to be a critically safe set of conditions for that piece of equipment, that is, 1) in a given and specified operational position where adjacent nuclear criticality interaction conditions are known and unchanging, 2) for a given and specified set or range of operating conditions, and 3) for a given and specified process.
The equipment can neither be accessed directly for purposes of operation or maintenance, nor can the equipment be viewed directly, for example, without intervening shielded viewing windows, periscopes, or a television monitoring system.
This guide is intended to be applicable to the design of equipment for the processing of materials containing uranium and transuranium elements in any physical form under the following conditions:
Such materials constitute an unacceptable radiation hazard to the operators and maintenance personnel,
The need exists for the confinement of the in-process material, of dusts and particulates, or of vapors and gases arising or resulting from the handling and processing of such materials, and
Any of the conditions cited in 1.2.1 apply.
This guide is intended to apply to the design, fabrication, and installation of ancillary and support services equipment under the following conditions:
Such equipment is installed in shielded cell or canyon environments, or
Such equipment is an integral part of an in-cell processing equipment configuration, or an auxiliary component or system thereof, even though an equipment item or system may not directly hold or contain nuclear or radioactive materials under normal processing conditions.
NOTE 1-Upsets, accidents, or certain emergency conditions may be specified (and thus required) design considerations, but not necessarily acceptable or normal operating circumstances under this definition
This guide is intended to apply to the design and fabrication of any and all types of equipment for radioactive wastes processing when any of the conditions cited in 1.2.1 apply. This would include equipment for waste concentration; for incorporation of wastes in selected host materials or matrices; and for the fixation, encapsulation, or canning of such wastes. It is intended to apply to all such wastes, regardless of the product waste composition or form. The product radioactive waste may have a glass, ceramic, metallic, concrete, bituminous, or other type of host material or matrices (composition), and may be in pelletized, solid, or granular form.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
NOTE 2-Warning: This standard pertains to equipment used in and for the handling and processing of nuclear and radioactive materials. These operations are known to be hazardous for a variety of reasons, one being chemical toxicity.
This standard is not a substitute for applied engineering skills. Its purpose is to provide guidance.
The guidance set forth in this standard relating to design of equipment is intended only to alert designers and engineers to those features, conditions, and procedures that have been found necessary or highly desirable to the acquisition of reliable equipment for the subject service conditions.
The guidance set forth results from discoveries of conditions, practices, features, or lack of features that were found to be sources of operational or maintenance trouble, or causes of failure.
It is often necessary to maintain the materials being processed within specific chemical composition or concentration ranges, or both. When such constraints apply, it may also be necessary to create and maintain a specific geometric array to minimize the chances of a nuclear criticality incident. Designers and engineers are referred to other standards for additional guidance when such requirements apply.
Equipment usage intent, service conditions, size and configuration, plus the configuration and features of the operating and maintenance environments have an influence on equipment design. Therefore, not all of the criteria, conditions, caveats, or features would be applicable to every equipment item.
It is intended that equipment designed, fabricated, procured, or obtained by transfer or adaptation and re-use of existing equipment, and installed in accord with the standard meet or exceed statutory, regulatory, and safety requirements for that equipment under the applicable operating and service conditions.
This standard does not supersede federal or state regulations, or both, and codes applicable to equipment under any conditions.