ASTM E2450-16
Standard Practice for Application of CaF2(Mn) Thermoluminescence Dosimeters in Mixed Neutron-Photon Environments

Standard No.

ASTM E2450-16

Release Date

2016

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM E2450-23

Latest

ASTM E2450-23

Scope

4.1 Electronic devices are typically tested for survivability to gamma radiation in pure gamma-ray fields. Testing electronic device response against neutrons is more complex since there is invariably a gamma-ray component in addition to the neutron field. The gamma-ray response of the electronic device is typically subtracted from the overall response to find the device response to neutrons. This approach to the testing requires a determination of the gamma-ray exposure in the mixed field. To enhance the neutron effects, the radiation field is sometimes selected to have as large a neutron component as possible.

4.2 CaF₂(Mn) TLDs are often used to monitor the gamma-ray dose in mixed neutron/gamma radiation fields. Since the dosimeters are exposed along with the device under test to the mixed field, their response must be corrected for neutrons. In a field rich in neutrons, the uncertainty in the interpretation of the TLD response grows. In fields with relatively few neutrons, the total TLD response may be used to make a correction for gamma response of the device under test. Under this condition, the relative uncertainty in the TLD neutron response is not likely to drive the overall uncertainty in the correction to the electronic device response.

4.3 This practice gives a means of estimating the response of CaF₂(Mn) TLDs to neutrons. This neutron response is then subtracted from the measured response to determine the TLD response due to gamma rays. The procedure has relatively high uncertainty because the neutron response of CaF₂(Mn) TLDs may vary depending on the source of the material, and this procedure is a generic calculation applicable to CaF₂(Mn) TLDs independent of their manufacturer/source. The neutron response given in this practice is a summary of CaF₂(Mn) TLD responses reported in the literature. The associated uncertainty envelops the range of results reported, and includes the variety of CaF₂(Mn) TLDs used as well as the uncertainties in the determination of the neutron response as reported by various authors.

4.4 Should the user find the resulting uncertainties too large for his purposes, the neutron response of the particular CaF₂(Mn) TLDs in use must be determined. This practice does not supply guidance on how to determine the neutron response of a specific batch of TLDs.

4.5 Neutron effects on electronics under test are usually reported in terms of 1-MeV(Si) equivalent fluence (E722). Neutron effects of TLDs, as discussed here, are reported in units of absorbed dose, since they are corrections to the gamma-ray dose.

1.1 This practice describes a procedure for correcting a CaF₂(Mn) thermoluminescence dosimeter (TLD) reading for its response to neutrons during the irradiation. The neutron response may be subtracted from the total TLD response to give the gamma-ray response. In fields with a large neutron contribution to the total response, this procedure may result in large ......

ASTM E2450-16 Referenced Document

• ASTM E170 Standard Terminology Relating to Radiation Measurements and Dosimetry
• ASTM E1854 Standard Practice for Ensuring Test Consistency in Neutron-Induced Displacement Damage of Electronic Parts
• ASTM E666 Standard Practice for Calculating Absorbed Dose From Gamma or X Radiation
• ASTM E668 Standard Practice for Application of Thermoluminescence-Dosimetry (TLD) Systems for Determining Absorbed Dose in Radiation-Hardness Testing of Electronic Devices
• ASTM E720 Standard Guide for Selection and Use of Neutron-Activation Foils for Determining Neutron Spectra Employed in Radiation-Hardness Testing of Electronics
• ASTM E721 Standard Guide for Determining Neutron Energy Spectra from Neutron Sensors for Radiation-Hardness Testing of Electronics
• ASTM E722 Standard Practice for Characterizing Neutron Energy Fluence Spectra in Terms of an Equivalent Monoenergetic Neutron Fluence for Radiation-Hardness Testing of Electronics
• ASTM F1190 Standard Guide for Neutron Irradiation of Unbiased Electronic Components

ASTM E2450-16 history

• 2023 ASTM E2450-23 Standard Practice for Application of CaF2(Mn) Thermoluminescence Dosimeters in Mixed Neutron-Photon Environments
• 2016 ASTM E2450-16 Standard Practice for Application of CaF2(Mn) Thermoluminescence Dosimeters in Mixed Neutron-Photon Environments
• 2011 ASTM E2450-11 Standard Practice for Application of CaF₂(Mn) Thermoluminescence Dosimeters in Mixed Neutron-Photon Environments
• 2006 ASTM E2450-06 Standard Practice for Application of CaF2(Mn) Thermoluminescence Dosimeters in Mixed Neutron-Photon Environments
• 2005 ASTM E2450-05 Standard Practice for Application of CaF2(Mn) Thermoluminescence Dosimeters in Mixed Neutron-Photon Environments