Fissionable Material Outside Reactors (ANS-8)

  • ANS-8.1, Nuclear Criticality Safety in Operations with Fissionable Materials Outside Reactors
    Scope: This standard is applicable to operations with fissionable materials outside nuclear reactors, except for the assembly of these materials under controlled conditions, such as in critical experiments. Generalized basic criteria are presented and limits are specified for some single fissionable units of simple shape containing 233U, 235U, or 239Pu, but not for multiunit arrays. Requirements are stated for establishing the validity and areas of applicability of any calculational method used in assessing nuclear criticality safety. This standard does not include the details of administrative controls, the design of processes or equipment, the description of instrumentation for process control, nor detailed criteria to be met in transporting fissionable materials.
  • ANS-8.3, Criticality Accident Alarm System
    Scope: This standard is applicable to all operations involving fissionable materials in which inadvertent criticality can occur and cause personnel to receive unacceptable exposure to radiation. This standard is not applicable to detection of criticality events where no excessive exposure to personnel is credible, nor to nuclear reactors or critical experiments. This standard does not include details of administrative actions or of emergency response actions that occur after alarm activation.
  • ANS-8.5, Use of Borosilicate-Glass Raschig Rings as a Neutron Absorber in Solutions of Fissile Material
    Scope: This standard provides guidance for the use of borosilicate-glass Raschig rings as a neutron absorber for criticality control in ring-packed vessels containing solutions of 235U, 239Pu, or 233U. The chemical and physical environment, properties of the rings and packed vessels, maintenance inspection procedures, and operating guidelines are specified.
  • ANS-8.6, Safety in Conducting Subcritical Neutron-Multiplication Measurements in Situ
    Scope: This standard provides safety guidance for conducting subcritical neutron-multiplication measurements where physical protection of personnel against the consequences of a criticality accident is not provided. The objectives of in situ measurements are either to confirm an adequate safety margin or to improve an estimate of such a margin. The first objective may constitute a test of the criticality safety of a design that is based on calculations. The second may affect improved operating conditions by reducing the uncertainty of safety margins and providing guidance to new designs.
  • ANS-8.7, Nuclear Criticality Safety in the Storage of Fissile Materials
    Scope: This standard is applicable to the storage of fissile materials. Mass and spacing limits are tabulated for uranium containing greater than 30 wt-% 235U, for 233U, and for plutonium, as metals and oxides. Criteria for the range of application of these limits are provided.
  • ANS-8.10, Criteria for Nuclear Criticality Safety Controls in Operations with Shielding and Confinement
    Scope: This standard provides criteria that may be used for operations outside of nuclear reactors with 235U, 233U, 239Pu, and other fissile and fissionable materials in which shielding and confinement are provided for protection of personnel and the public, except for the assembly of these materials under controlled conditions (e.g., critical experiments). The standard does not include details of administrative procedures for control (i.e., management prerogatives) nor details regarding design of processes and equipment or descriptions of instrumentation for process control.
  • ANS-8.12, Nuclear Criticality Control and Safety of Plutonium-Uranium Fuel Mixtures Outside Reactors
    Scope: This standard is applicable to operations with homogeneous mixtures of plutonium and uranium. The mixtures may be solutions, suspended solids, precipitates, or may have been formed mechanically. Basic criteria are presented for plutonium-uranium fuel mixtures containing no more than 30 wt% plutonium combined with uranium containing no more than 0.71 wt% 235U. This standard does not include the details of administrative controls, the design of processes or equipment, the description of instrumentation for process control, or detailed criteria to be met in transporting fissionable materials. The limits of this standard are not applicable to heterogeneous systems such as lattices of rods in water, mixtures in which particles are large enough to introduce lumping effects, or mixtures in which the concentrations of components are nonuniform. The limits are applicable, however, to homogeneous mixtures and slurries in which the particles constituting the mixture are uniformly distributed and have a diameter no larger than 127 mm (0.005 in.), i.e., are capable of being passed through a 120 mesh screen.
  • ANS-8.14, Use of Soluble Neutron Absorbers in Nuclear Facilities Outside Reactors
    Scope: This standard provides guidance for the use of soluble neutron absorbers for criticality control. This standard addresses neutron absorber selection, system design and modifications, safety evaluations, and quality control programs.
  • ANS-8.15, Nuclear Criticality Safety Control of Selected Actinide Nuclides
    Scope: This standard is applicable to operations with the following nuclides: 232U, 234U, 237Np, 236Pu, 238Pu, 240Pu, 241Pu, 242Pu, 241Am, 242mAm, 243Am, 242Cm , 243Cm, 244Cm, 245Cm, 246Cm, 247Cm, 249Cf and 251Cf. Subcritical mass limits are presented for isolated units. The limits are not applicable to interacting units.
  • ANS-8.17, Criticality Safety Criteria for the Handling, Storage and Transportation of LWR Fuel Outside Reactors
    Scope: This standard provides nuclear criticality safety criteria for the handling, storage, and transportation of LWR fuel rods and units outside reactor cores.
  • ANS-8.19, Administrative Practices for Nuclear Criticality Safety
    Scope: This standard provides criteria for the administration of a nuclear criticality safety program for outside-of-reactor operations in which there exists a potential for criticality accidents. Responsibilities of management, supervision, and the nuclear criticality safety staff are addressed. Objectives and characteristics of operating and emergency procedures are included.
  • ANS-8.20, Nuclear Criticality Safety Training
    Scope: This standard provides criteria for nuclear criticality safety training for personnel associated with operations outside reactors where a potential exists for criticality accidents. It is not sufficient for the training of nuclear criticality safety staff.
  • ANS-8.21, Use of Fixed Neutron Absorbers in Nuclear Facilities Outside Reactors
    Scope: This standard provides guidance for the use of fixed neutron absorbers as an integral part of nuclear facilities and fissionable material process equipment outside reactors, where such absorbers provide criticality safety control.
  • ANS-8.22, Nuclear Criticality Safety Based on Limiting and Controlling Moderators
    Scope: This standard applies to limiting and controlling moderators to achieve criticality safety in operations with fissile materials in a moderator control area. This standard does not apply to concentration control of fissile materials.
  • ANS-8.23, Nuclear Criticality Accident Emergency Planning and Response
    Scope: This standard provides criteria for minimizing risks to personnel during emergency response to a nuclear criticality accident outside reactors. This standard applies to those facilities for which a criticality accident alarm system, as specified in American National Standard "Criticality Accident Alarm System", ANSI/ANS-8.3-1997 (R2003) [1],1) is in use. This standard does not apply to nuclear power plant sites or to licensed research reactor facilities, which are addressed by other standards.
  • ANS-8.24, Validation of Neutron Transport Methods for Nuclear Criticality Safety Calculations
    Scope: This standard provides requirements and recommendations for validation, including establishing applicability, of neutron transport calculational methods used in determining critical or subcritical conditions for nuclear criticality safety analyses.
  • ANS-8.26, Criticality Safety Engineer Training and Qualification Program
    Scope: This standard presents the fundamental content elements of a training and qualification program for individuals with responsibilities for performing the various technical aspects of criticality safety engineering. The standard presents a flexible array of competencies for use by management to develop tailored training and qualification programs applicable to site-specific job functions, facilities and operations.
  • ANS-8.27, Burnup Credit for LWR Fuel
    Scope: The standard provides criteria for processes and techniques used for criticality safety evaluations of irradiated light water reactor fuel assemblies in storage, transportation and disposal.
  • ANS-8.28, Administrative Practices for the Use of Non-Destructive Assay Measurements for Nuclear Criticality Safety
    Scope: This standard provides administrative practices covering the interface between the criticality safety community and the NDA community including in-situ measurements and measurements of containerized materials.