Depends on your perspective. From a risk management perspective the logical choice would be no since the likelihood of it being real is infinitesimally small (these are typically related to either an employee who doesn't want to go in on the next shift or who wants to leave early, and they or a family member of friend calls in the scare; might also just be a disgruntled employee/citizen). However, the impact if it's real and bomb explodes is very high, so legal risk would cause most to evacuate.
And in the US I'd guess most would evacuate if for no other reason than to avoid the new media circus that might result if they don't (and perhaps even if they do). Much of the media is not in the business of informing, but instead inciting.
I agree with Duke Okes, there's no hard and fast good answer. His examples are good. I would only add that it also depends on the nature, size, and complexity of the organization. We do a lot of DoD work and would have to make sure things were adequately locked down before any type of evacuation. That said, we could probably do so and get everyone out in less than 10 minutes so we would probably evacuate.
Not sure if that helps or complicates it for you.
Amanda Foster, ASQ CQA
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