Document: NUREG-0800
Document ID: 2b4d3a5f-8e25-4c13-a035-954d864e0c14
Document Type: srp
Title: MISSILES GENERATED BY NATURAL PHENOMENA
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340526.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.5.1.4
CFR Part: 
CFR Title: 

Content:
est from the primary reviewer, SEB will provide, input for the areas of review stated in subsection I. The primary reviewer obtains and uses such input as required to assure that this review procedure is complete. The reviewer will select and emphasize material from this SRP section, as may be appropriate for a particular case. The judgment on areas to be given attention and emphasis in the review is to be based on an inspection of the material presented to see whether it is similar to that recently' reviewed on other plants and whether items of special safety significance are involved. .1 The SAR is reviewed for the identification of the design basis natural phenomena which could possibly generate missiles. Postulated missiles are reviewed for proper characterization. 2. The probability per year of damage to the total of all important struc- tures, systems, and components (as discussed in Regulatory Guide 1.117) due to a specific design basis natural phenomena capable of generating missiles is estimated. 3.. If this probability is greater than the acceptable probability stated in Regulatory Guide 1.117, then specific design provisions must be provided to reduce the estimate of damage probability to an allowable level. 4. All plants are required to be designed to protect safety-related equipment against damage from missiles which might be generated by the design basis tornado for that plant. The reviewer verifies that the applicant has postu- | lated missiles that include at least three objects: a massive high kinetic energy missile which deforms on impact, a rigid missile to test penetration resistance, and a small rigid missile of a size sufficient to just pass through any openings in protective barriers. Until more definitive guide- lines are established, these missiles may be assumed to be an 1800 Kg automobile, a 125. Kg 8".armor piercing artillery shell, and a 1" solid steel sphere, all impacting at 35% of the maximum horizontal windspeed of the design basis