Tritium Dose and Exposure Data

DOE-HDBK-1129-99

Facility Categories

- Hazard Category 1: Category A reactors and facilities designated by PSO.

- Hazard Category 2: > 30 g of tritium

- Hazard Category 3: > 1.6 but < 30 g of tritium

- Radiological Facility:< 1.6 g of tritium

A.3 Tritium Dose and Exposure Data

Biological half-life = 8 to 12 days (oxide); biological half-life of tritides is currently being

researched

Derived Air Concentration (DAC)

- DAC for HTO = 21.6 Ci/m3 = 2 x 10-5 Ci/mL = 8 x 105 Bq/m3

- DAC for HT = 540,000 Ci/m3 = 5 x 10-1 Ci/mL = 2 x 1010 Bq/m3

No DACs currently exist for tritides; efforts are underway to develop these

Dose Conversion Factor (DCF)

- DCF = 0.063 mrem/Ci (inhalation)

- DCF = 0.095 mrem/Ci (inhalation plus 50 percent allowance for skin absorption)

Annual Limit of Intake (ALI)

- ALI for HTO = 80,000 Ci

- An initial exposure equilibrium urine count of 1 Ci/L equates to approximately a

3-mrem dose.

- A urine count of 50 Ci/L for a year equates to approximately a 5,000-mrem dose.

- Breathing 21.6 Ci/m3 HTO in air for 8 hours/day, 50 week/year will result in a dose

of approximately 5,000 mrem.

- Tritiated water is approximately 25,000 times more hazardous than tritium gas

because of rapid uptake mechanisms.

Tritium Beta Particles

- Range in Air = 4.5 to 6 mm

- Range in Water = 0.0005 cm

- Range in Tissue = 0.0007 cm

- Radiation, 1 mCi in man (70 kg) = 0.0044 rem/day

- Maximum Penetration = 0.6 mg/cm3

A.4 Tritium Container Data

WSRC Hydride Transport Vessel (HTV)

- Reusable container for transporting up to 18 grams of tritium

- Shipped in UC-609

- Dual port, flow through capable

- One female, one male port, Cajon SS-4-VCR

- Tritium stored as uranium tritide

- Contains 493 g depleted uranium

- Stoichiometry Maximum 1:2.9

- Weight 9.3 lb

- Height 9.995 in

- Diameter 4.6 in

- Volume 690 cm3

- Maximum normal operating temperature = 450oC

- Pressure Limit at Maximum normal operating temperature = 2.9 psia

- Tritium vapor pressure as a function of temperature at U:T = 1:2.9

A-3