Specialized Instrumentation

DOE-HDBK-1129-99

Glovebox Atmosphere Monitors -- Glovebox monitors may be open mesh or closed ionization

chambers and are designed to monitor the higher levels of tritium inside the glovebox

containment systems.

Hood and Exhaust Duct, Air Monitors -- Hood and exhaust duct air monitors are similar to

fixed station monitors in range and characteristics.

Exhaust Stacks, Air Monitors -- Exhaust stack monitors are similar to fixed station air monitors

except that they generally have larger ionization chambers to increase the sensitivity of the

monitor.

Personnel Friskers and Breath Analyzers -- There has been some interest in instruments

which can be used to frisk personnel as they enter and exit tritium contaminated areas. One

DOE facility implemented a process of personnel frisking consisting of the use of skin surface

wipes counted in a liquid scintillation counter upon entry and exit from tritium contaminated

areas. In another facility, a hand station based on counting the associated gas flow across the

hands was used. To date, the development work required to relate measurements made by

these techniques to dose or worker exposure has not been completed. It is expected that

differences in the body chemistry of personnel and differences in the time delay between tritium

exposure and equilibration of tritium in the body will continue to make the results of skin

surface contamination measurement and breath analysis monitoring inconsistent. The impact

of false alarms and inconsistent results on worker confidence will probably continue to make

these systems unsatisfactory for worker monitoring.

5.9.2 Specialized Instrumentation

There are many other types of specialized devices and/or instrumentation vendors, and some may

be superior to those discussed here. No endorsement of these devices should be inferred by the

reader. A more expansive discussion is planned for the next revision of this Handbook.

5.9.2.a Remote Field Tritium Analysis System

A prototype system for the remote, in situ analysis of tritium in surface and ground waters has

been developed at SRS. Using automated liquid scintillation counting techniques, the Field

Deployable Tritium Analysis System (FDTAS) has been shown in laboratory and field tests to have

sufficient sensitivity to measure tritium in water samples at environmental levels (10 becquerels

(Bq)/L [~270 pCi/L] for a 100-minute count) on a near-real-time basis.

The prototype FDTAS consists of several major components: a muti-port, fixed volume sampler, an

on-line water purification system using single-use "tritium columns," a tritium detector employing

liquid scintillation counting techniques, and the serial communications devices. The sampling and

water purification system, referred to as the "autosampler," is controlled by a Programmed Logic

Controller pre-programmed to perform a well-defined sampling, purification, and flushing protocol.

The tritium analyzer contains custom software in the local computer for controlling the mixing of the

purified sample with liquid scintillation cocktail, counting, and flushing the cell. An external

standard is used to verify system performance and for quench correction. All operations are

initiated and monitored at the remote computer through standard telephone line modem