Mound Technical Solutions

BSD

BSD

© 2011 Mound Technical Solutions

Tritium Beta Scintillation Detectors

The beta scintillation detector (BSD) is used to measure a photocurrent that is linearly proportional to the
partial pressure of tritium. Figure 1 shows the BSD sensitivity versus gas pressure; the sensitivity is
constant (within 1%) which is linear response for pressures up to 10 Torr

Fig. 1. BSD sensitivity versus sample pressure for HDT-He
samples (n) and HDT-He with 10% N2 (s) samples.

When calibrated to give tritium partial pressure
from a sensitivity, S(Volts/Torr-T2), the mole
percentage of total tritium can be computed:

where [P- P0] is the total sample pressure. The gas measurement condition that is necessary for linear response of the BSD is low pressure (< 10 Torr) such that absorption of the beta energy by the gas is minimal (about 1% or less) or predictable.

where [P- P0] is the total sample pressure. The gas measurement condition that is necessary for linear response of the BSD is low pressure (< 10 Torr) such that absorption of the beta energy by the gas is minimal (about 1% or less) or predictable.

Fig. 2.

A Basic Analytical System for BSD measurement of process tritium

A Basic Analytical System for BSD measurement of process tritium