Parameter Assumptions

DOE-STD-3014-96

APPENDIX D

credit for these systems should not be taken unless it can be clearly

supported by analyses.

It is not expected that an explosion will occur except in the case of

systems having an existing explosive potential, such as an ion exchange

column or weapons components. Where such systems exist and are

subject to events with the potential to act as initiators, an explosion will be

assumed to occur. Such explosions may serve as initiators for

subsequent releases beyond those expected from the aircraft crash itself,

particularly in cases where kinetic energy released from an explosion has

the potential to impact material that otherwise would not be impacted (e.g.,

material not within areas directly impacted by aircraft debris). Therefore,

postulating an explosion requires a re-evaluation of damage ratio

assumptions, since explosions may disable barriers otherwise assumed to

function, and may produce secondary energetic effects (e.g., due to

shrapnel or collapsing structural members). For example, fire barriers on

robust containments that would otherwise remain intact may be breached

or compromised.

ARFij/ARRij/RFij - Bounding values for nuclear materials are based on

guidance developed by the U.S. Department of Energy (Reference 1). The

use of bounding values, as opposed to best estimates, is specified due to

the variability and limited quantity of experimental data from which

analytically useful values can be derived. In addition, due to the limited

data available, the variety of experimental conditions from which individual

bounding values are derived, and the general lack of precise

correspondence between experimental conditions and conditions assumed

for analysis, statistical analysis is not considered appropriate when using

data from DOE-HDBK-3010-94 for the purpose of aircraft crash

evaluations. Specific applications considered inappropriate include the

use of best estimate values or the

D-2