Material Release Assumptions

DOE-HDBK-1129-99

significant class fire suppression will affect the selection of the credible facility fire scenario and

therefore the fire conditions for comparison to the transportation fire conditions.

If the transportation accident conditions are less severe than the facility accident conditions, then

the contents are included in the accident scenarios. For example, if the seismic crush loads

exceed the transportation crush loads, the contents cannot be excluded from the facility seismic

accident scenarios. They could, however, still be excluded from the facility fire scenarios if the

transportation fire conditions bound the facility fire conditions.

DOE-STD-1027-92 Change Notice 1 does not provide explicit exemption criteria for other than

Type B containers. Future guidance for other than Type B containers, in addition to the guidance

concerning the degree and amount of residual tritium inventory to include in safety analyses, will

be included in the next revision of this handbook.

The threshold quantities of radiological material inventory [18-20] are as follows:

Hazard Category I: (Nuclear Facility) Generally Limited to Nuclear Reactors: Regardless of the

quantity of tritium in the inventory, a facility that handles only tritium is not classified, by tritium

quantity alone, as a Hazard Category I. The PSO may designate a tritium facility as Category I

if the potential for significant offsite consequences exists. [18]

Hazard Category II: (Nuclear Facility): To be classified as a Category II nuclear facility, the

facility tritium inventory must be > 30 grams. [18]

Hazard Category III: (Nuclear Facility): To be classified as a Category III nuclear facility, the

facility tritium inventory must be > 1.6 and < 30 grams. [18]

Radiological Facilities: (Not Nuclear Facilities): Facilities that have less than 1.6 grams of

tritium in the facility radiological material inventory are not classified as "nuclear facilities,"

unless they contain higher than threshold values of other radionuclides. These facilities are

classified as radiological facilities. [18]

Non-Radiological Facilities: Facilities that have less than 100 Ci of tritium are classified by the

DOE Offices of Defense Programs (DP) and Environmental Management (EM) as non-

radiological facilities, unless they contain other radionuclides above reportable quantities. [19,

20]

3.3.1.c Material Release Assumptions

Once the total inventory available for release is known, the appropriate source term can be

calculated. The components of the source term, as described in DOE-HDBK-3010-94, "Airborne

Release Fraction/Rates and Respirable Fractions for Nonreactor Nuclear Facilities," are material at

risk, damage ratio, airborne release fraction, respirable fraction, and leakpath factor. The factors

for airborne release and respirable fractions are normally assumed to be 1.0 for elemental tritium

and oxide. The other factors are facility specific. For fire scenarios, the fraction of the release

assumed to be oxide is normally 100 percent. Typical scenarios to review for inclusion in safety

analyses are area fires (single and multiple Fire Control Areas (FCA)), full facility fire, leaks/spills,

hydrogen explosions, and Natural Phenomena Hazards (NPH) events (the design basis

earthquake (DBE) may have a seismic induced fire, which usually results in the bounding