ASTM C788-03(2021) PDF

Overview

ASTM C788-03(2021) - Standard Specification for Nuclear-Grade Uranyl Nitrate Solution or Crystals provides essential criteria for nuclear-grade aqueous uranyl nitrate solution or crystals, each containing no more than 5% 235U. This specification supports the nuclear industry by defining impurity and uranium isotope limits for both commercial and reprocessed uranyl nitrate, whether used as a precursor for uranium hexafluoride (UF6) or for direct conversion to uranium oxide (UO2) for reactor fuel. Developed according to internationally recognized principles, ASTM C788 sets baseline requirements for material quality, safety, and traceability, accommodating the diversity of manufacturing and processing methods in the nuclear fuel cycle.

Key Topics

• Scope and Coverage

  • Applies to uranyl nitrate solutions and crystals intended for UF6 production (nuclear fuel enrichment) or direct conversion to uranium oxide.
  • Specifies a limit of 5% maximum 235U content.
  • Considers both commercial and reprocessed uranyl nitrate, recognizing typical differences in impurity and isotope profiles.

• Impurity and Isotope Limits

  • Defines stringent impurity limits for elements such as antimony, boron, chlorine, fluorine, lead, thorium, silicon, and others, with separate tables for material destined for UF6 or UO2 end use.
  • Stipulates maximum uranium isotope concentrations for commercial and reprocessed products, with special requirements for products containing reprocessed uranium.
  • Addresses radionuclide content, including controls on gamma-emitting fission products and alpha activity from transuranic isotopes.

• Sampling and Analysis

  • Requires representative sampling and traceable identification of all material containers.
  • Analytical verification is mandated as a part of the manufacturer’s quality assurance and nuclear materials accountability programs.
  • Calls for use of validated chemical and isotopic analysis methods as per referenced ASTM standards or as mutually agreed.

• Regulatory and Safety Requirements

  • Emphasizes compliance with all international, federal, state, and local regulations regarding criticality safety, health, environmental protection, and shipping.
  • Referenced guides include the U.S. Code of Federal Regulations Title 10, Part 50 and ASME NQA-1 quality assurance standards.
  • Assigns responsibility for safety practice development and regulatory compliance to the user of the standard.

Applications

ASTM C788 is vital for:

• Nuclear Fuel Manufacturing:

  • Provides the foundational material specification for nuclear fuel producers who convert uranyl nitrate solution or crystals into uranium hexafluoride or directly into uranium oxide for reactor core fabrication.

• Commercial and Reprocessed Uranium Management:

  • Supports consistent characterization and control of uranyl nitrate whether derived from unirradiated uranium or reprocessed fuel.

• Regulatory and Quality Assurance Compliance:

  • Assists facilities in demonstrating conformance to material quality, safety, and traceability expectations required by national and international regulatory authorities.

• Supply Chain and Procurement:

  • Provides purchasers and suppliers with a clear, standardized basis for specifying and accepting nuclear-grade uranyl nitrate products.

Related Standards

• ASTM C787 - Specification for Uranium Hexafluoride for Enrichment
• ASTM C996 - Specification for Uranium Hexafluoride Enriched to Less Than 5% 235U
• ASTM C799 - Test Methods for Chemical, Mass Spectrometric, Spectrochemical, Nuclear, and Radiochemical Analysis of Nuclear-Grade Uranyl Nitrate Solutions
• ASTM C859 - Terminology Relating to Nuclear Materials
• ASTM C1233 - Practice for Determining Equivalent Boron Contents of Nuclear Materials
• ASTM C1295 - Test Method for Gamma Energy Emission from Fission and Decay Products in Uranium Hexafluoride and Uranyl Nitrate Solution
• ANSI/ASME NQA-1 - Quality Assurance Requirements for Nuclear Facility Applications
• Code of Federal Regulations, Title 10, Part 50 - Domestic Licensing of Production and Utilization Facilities

Keywords: uranyl nitrate, nuclear-grade, uranium solutions, uranium isotope limits, impurity limits, nuclear fuel, ASTM C788, uranium hexafluoride, uranium oxide, reprocessed uranium, nuclear industry standards.