Detailed Criteria for Wind Hazard Assessment

DOE-STD-1023-95

3.2 Detailed Criteria for Wind Hazard Assessment

3.2.1 General

Design and evaluation criteria for DOE facilities against wind hazards are provided by DOE-STD-

2002. In accordance with DOE-STD-1020-2002, (1) the recommended basic wind speed for all

PCs; (2) the atmospheric pressure change (APC) associated with a tornado for PC 3 or 4 SSCs; and

(3) windborne missile criteria (size, weight, and speed) for PC 3 or 4 SSCs; shall be defined in order

to carry out the design/evaluation process.

Criteria for the atmospheric pressure change and recommended windborne missiles are contained in

DOE-STD-1020-2002.

The recommended basic wind speed shall be determined from a mean wind hazard curve developed

for the site in accordance with the hazard annual probability specified in DOE-STD-1020-2002. The

recommended basic wind speeds for 25 DOE sites have been modified from ASCE 7-98 requirements

in DOE-STD-1020-2002. DOE O 420.1 requires that the need for updating the site wind hazard

assessment be reviewed at least every 10 years. Therefore, for sites where existing wind hazard

assessments are either unavailable or considered out of date, a new wind hazard assessment shall be

conducted.

The purpose of this Section of the Standard is to provide specific criteria for the DOE facilities with

respect to the wind hazard assessment. The criteria are provided to ensure that a consistent approach

across DOE sites is achieved for design/evaluation of DOE facilities against wind hazards.

For sites containing facilities with SSCs in only PC 1 or 2, missile effects and atmospheric pressure

change due to tornadoes need not be considered. Therefore, the only wind hazard design parameter

to be established is the basic wind speed.

For sites having no site-specific probabilistic wind hazard assessment, it is sufficient to utilize

model building codes, or national consensus standards, such as ASCE (1998a), to define the

basic wind speed.

For sites which have site-specific probabilistic wind hazard assessment, the SSCs in PC 1 or 2

shall be evaluated for the greater of the site-specific values or the model code values unless

lower site-specific values can be justified and approved by DOE.

For sites containing facilities with SSCs in PC 3 or 4, a site-specific probabilistic wind hazard

assessment is conducted to establish the wind speed for design and/or evaluation of the facilities.

3.2.2 Criteria for Site-Specific Probabilistic Wind Hazard Assessment

For facilities with SSCs in PC 3 or 4, a site-specific probabilistic wind hazard assessment is

conducted to establish the wind speed.