English to Chinese Tech/Engineering IT (Information Technology) disaster recovery

Dave Raspallo, director of receivable systems, is responsible for TFC's recovery planning effort. He says his organization tried to follow the multi-threat approach initially but found that managers were overwhelmed by the prospect of planning for every possible calamity. Instead, Raspallo devised a simplified approach that encompasses four levels of business interruption or consequences that could result from disasters, as follows:
* Level one--Building destroyed or unusable for business activity
* Level two--One or more floors unusable, but recovery possible within building
* Level three--A single company department lost, but recovery possible within building
* Level four--A single {function} or workstation lost, but recovery possible on same floor
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