The U.S. Office of Personnel Management (OPM) has prepared human resources guidance for agencies and employees on shutdown furloughs (also called emergency furloughs).
A shutdown furlough occurs when there is a lapse in annual appropriations. Shutdown furloughs can occur at the beginning of a fiscal year, if no funds have been appropriated for that year, or upon expiration of a continuing resolution, if a new continuing resolution or appropriations law is not passed.
Click the link to see entire document: http://www.opm.gov/policy-data-oversight/pay-leave/furlough-guidance/guidance-for-shutdown-furloughs.pdf
Click to view DoD Shutdown Guidance: http://www.defense.gov/home/features/2013/0913_govtshutdown/