Any company can have threats to its existence. Economic threats are the ones that a company usually worries over the most. The nature of physical threats is that they can have a long-term impact. However, you must gauge a physical threat against the likelihood that it will occur. For example, take a physical threat like a fire or tornado hitting the building(s) that house a business; is such a threat real? Possibly, but it is also remote.
On the other hand, some threats, like a break-in, are not as remote; and the threat may not be as devastating as a fire.
To handle physical security and threat assessments, a security engineer should look at how the physical threat could manifest itself. Then he can decide how to address such an issue. In most cases, if the threat is that devastating, then the security engineer should develop a disaster recovery plan.

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