ABSTRACT

To determine the elemental tritium content of the air, process the nal trap according to Method 3, Sections 9.6 through 9.10.

Refer to Section 10 of Method 3 and follow instructions.

10.1 Efciency:

EFF

CR ACT

= − R ,

(1)

where EFF is the counting efciency (cpm dpm−1), CRSTD is the gross count rate (counts per minute or cpm) of standard in scintillation solution, RB is the background count rate (cpm) of distilled water in scintillation solution, and ACTSTD is the disintegrations per minute (dpm) of standard.