ASTM C1493-09
Standard Test Method for Non-Destructive Assay of Nuclear Material in Waste by Passive and Active Neutron Counting Using a Differential Die-Away System

Standard No.

ASTM C1493-09

Release Date

2009

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM C1493-19

Latest

ASTM C1493-19

Scope

This test method is useful for quantifying fissile (for example, ²³³U, ²³⁵U, ²³⁹Pu and ²⁴¹Pu) and spontaneously-fissioning nuclei (for example, ²³⁸Pu, ²⁴⁰Pu, ²⁴²Pu, ²⁴⁴Cm, ²⁴⁸Cm, and ²⁵²Cf) in waste and scrap drums. Total elemental mass of the radioactive materials can be calculated if the relative abundances of each radionuclide are known.

Typically, this test method is used to measure one fissile isotope (for example, ²³⁵U or ²³⁹Pu).

This test method can be used to segregate low level and transuranic waste at the 100 nCi/g concentration level currently required to meet the DOE Waste Isolation Pilot Plant (WIPP) waste acceptance criterion (5, 8, 9).

This test method can be used for waste characterization to demonstrate compliance with the radioactivity levels specified in waste, disposal, and environmental regulations (See NRC regulatory guides, DOE Order 435.1, 10 CFR Part 71, 40 CFR Part 191, and DOE /WIPP-069).

In the active mode, the DDT system can measure the ²³⁵U content in the range from <0.02 to >100 g and the ²³⁹Pu content, nominally between <0.01 and >20 g.

In the passive mode, the DDT system is capable of assaying spontaneously-fissioning nuclei, over a nominal range from 0.05 to 15 g of ²⁴⁰Pu, or equivalent (5, 10, 11, 12, 13).

This test method should be used in conjunction with a waste management plan that segregates the contents of assay items into material categories according to some or all of the following criteria: bulk density of the waste, chemical forms of the plutonium or uranium and matrix, (α, n) neutron intensity, hydrogen (moderator) and absorber content, thickness of fissile mass(es), and the assay item container size and composition. Each matrix may require a different set of calibration standards and may have different mass calibration limits. The effect on the quality of the assay (that is, minimizing precision and bias) can significantly depend on the degree of adherence to this waste management plan.

The bias of the measurement results is related to the fill height, the homogeneity and composition of the matrix, the quantity and distribution of the nuclear material, and the item size. The precision of the measurement results is related to the quantity of the nuclear material, the background, and the count time of the measurement.

For both matrix-specific and wide-range calibrations, this test method assumes the calibration material matches the items to be measured with respect to homogeneity and composition of the matrix, the neutron moderator and absorber content, and the quantity, distribution, and form of nuclear material, to the extent they affect the measurement.

The algorithms for this test method assume homogeneity. Heterogeneity in the distribution of nuclear material, neutron moderators, and neutron absorbers has the potential to cause biased results (14).

This test method assumes that the distribution of the contributing radioisotopes is uniform throughout the container and that lumps of nuclear material are not present.

Reliable results from the application of this test method require waste to be packaged so the conditions of Section 5.5 can be met. In some cases, site-specific requirements will dictate the packaging requirements with possible detrimental effects to the measurement results.

Both the active mode and the passive mode provide assay values for plutonium. During the calibration process, the operator should determine the applicable mass ranges for both modes of operation.

1.1 This test method covers a sy......

ASTM C1493-09 Referenced Document

• ASTM C1030 Standard Test Method for Determination of Plutonium Isotopic Composition by Gamma-Ray Spectrometry
• ASTM C1207 Standard Test Method for Nondestructive Assay of Plutonium in Scrap and Waste by Passive Neutron Coincidence Counting
• ASTM C1215 Standard Guide for Preparing and Interpreting Precision and Bias Statements in Test Method Standards Used in the Nuclear Industry
• ASTM C1490 Standard Guide for the Selection, Training and Qualification of Nondestructive Assay (NDA) Personnel
• ASTM C1592 Standard Guide for Nondestructive Assay Measurements
• ASTM C1673 Standard Terminology of C26.10 Nondestructive Assay Methods*， 2024-04-19 Update

ASTM C1493-09 history

• 2019 ASTM C1493-19 Standard Test Method for Non-Destructive Assay of Nuclear Material in Waste by Passive and Active Neutron Counting Using a Differential Die-Away System
• 2009 ASTM C1493-09 Standard Test Method for Non-Destructive Assay of Nuclear Material in Waste by Passive and Active Neutron Counting Using a Differential Die-Away System
• 2001 ASTM C1493-01 Standard Test Method for Non-Destructive Assay of Nuclear Material in Waste by Passive and Active Neutron Counting Using a Differential Die-Away System