Low Pressure (0.35 MPag or less)

DOE-HDBK-3010-94

3.0 Liquids; Summary

The ARF and RF values depend on the maximum liquid or vessel

failure pressure and the density of solution. Two regimes are defined

for liquid venting or vessel failure pressure. The first regime is

pressure equal to or less than 0.35 MPag (~ 50 psig). This value is

independent of solution density. The second regime is for pressures

greater than 0.35 MPag up to 3.45 MPag (~ 500 psig). In this regime

a distinction is made between general aqueous solutions and

concentrated heavy metal nitrate solutions such as uranium nitrate

hexahydrate (UNH) or plutonium nitrate. The distinction is gross, with

any solution having a density > ~ 1.2 g/cm3 being considered a

concentrated heavy metal solution. The highest release fraction is for

aqueous solutions.

Low Pressure (0.35 MPag or less)

Bounding (all solutions)

ARF 5E-5/RF 0.8

High Pressure (> 0.35 MPag)

Median (aqueous solution, density ~ 1 g/cm3)

ARF 3E-4/RF 0.9

Median (conc. heavy metal solution, density

> ~ 1.2 g/cm3)

ARF 2E-4/RF 0.3

Bounding (aqueous solution)

ARF 2E-3/RF 1.0

Bounding (conc. heavy metal solution)

ARF 1E-3/RF 0.4

If the containment failure is located above the critical freeboard height,

allowing rapid pressurization and depressurization, the ARF and RF

values may be significantly less than those noted above. For failures

below the critical freeboard height, a potential method for estimating

release fractions is discussed in subsection 3.2.2.3.2.B. However,

difficulty in defining a critical parameter, density of gas released,

precludes clear use of the method at this time. The values noted above

will be conservative for such cases.

Depressurization of liquid above boiling point. Three different values

are defined for flashing spray release based on the degree of superheat:

liquids with less than 50 oC superheat above the boiling point of the

liquid; liquids with superheats between 50 and 100 oC above the boiling

point of the liquid; and liquids with greater than 100 oC superheat. The

ARF appears to increase with decreasing source size and volume. The

values used in the experiments for these parameters are much below

Page 3-3