Release Frequency Screening.

DOE-STD-3014-96

For each of these aircraft types or subcategories, the impact

locations that could result in such facility damage.

For each such impact location, the level of damage that would result

from an impact, including (1) location and depth of penetration,

(2) identification of structural failures, (3) path and final location of

missiles, (4) post-crash location of fuel tanks, and (5) damage status

of SSCs of concern.

Release Frequency Screening. The release frequency screening is a simple,

3.4

conservative calculation. For this analysis, an aircraft category is considered to have no

effect on a facility only if no impact results in structure damage (i.e., damage does not

exceed the structural response guideline). Thus, if any impact from a given aircraft

subcategory will cause a release, then it is assumed that all impacts from that aircraft

subcategory will result in a release. Any aircraft subcategory considered to have no

effect on the facility is deleted from further consideration in the analysis. The release

frequency is calculated by summing the impact frequencies for all remaining aircraft

subcategories. Note that this calculation includes the impact frequencies of any aircraft

subcategories that have not been subject to a structural response analysis, unless it can

be documented that they will not cause sufficient damage to cause a release. The

methodology for the analysis is provided in Section 5.4. This result is compared to the

release frequency screening guideline provided in Section 4.4. If the guideline is not

exceeded, the results are documented. If the guideline is exceeded, the analysis should

proceed to the next step.

Inputs:

The release frequency screening guideline. (Defined)

A list of aircraft subcategories subjected to structural response analysis.

(Derived)

The annual aircraft impact frequency for all aircraft subcategories.

(Derived)

Accident scenario information. (Available from existing facility safety

analysis documents)