Contaminated, Noncombustible Solids

DOE-HDBK-3010-94

5.0 Surface Contamination; Summary

C on tam in ated , N on com b u stib le S olid s

T h erm al S tres s

Bounding values were selected based on reasoned judgement that the suspension of surface

contamination (most probably in the form of a sparse population of particles attached to the

surface) under thermal stress is bounded by the suspension of non-reactive powders under

thermal stress in a flowing airstream (see subsection 4.4.1.1).

Bounding

ARF 6E-3/RF 0.01

E xp losive S tres s

The values assessed to be bounding are based on reasoned judgment. No applicable data

were found. The effect most closely resembling stresses in a given explosive-type accident

scenario is chosen. There is no need to assume cumulative releases for all effects cited.

Shock Effects. For detonations in or contiguous to unyielding solid material, a

respirable release of the mass of inert material equal to the calculated TNT

equivalent is assessed to be bounding. At low mass ratios (mass inert

material/mass TNT equivalent), the respirable release is comparable to the

total material release. As mass ratios increase, the respirable fraction becomes

significantly less than the total amount of material released, which decreases

with increasing mass ratio as well.

Blast Effects. This phenomena is considered bounded by values assessed for

venting of pressurized gases over material discussed below.

Venting of Pressurized Gases Over Contaminated, Noncombustible Material.

The entrainment of the material is a function of the characteristics of the flow

over the particulate material that may be lying on the surface, the particles,

and the surface. Some of the flow characteristics are dependent on the initial

pressure and the size of the vent. If the solid is characterized only by loose,

externally deposited surface contamination, the release is characterized as to

whether the overall containment volume in which the contamination exists is

pressurized or not. If it is not, then the gases from the venting source are

considered bounded by the phenomena of accelerated airflow parallel to the

surface of powders (subsection 4.4.2.2.2.). If the volume is pressurized, the

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