Federal agencies this week are making plans for a potential shutdown if Congress and the White House fail to reach a deal on how to fund the government after Sept. 30.

(J. Scott Applewhite/AP) (J. Scott Applewhite/AP)

That planning isn’t done on a whim. The White House Office of Management and Budget has specific instructions on how executive agencies must prepare for and operate during a lapse in funding.

The Congressional Research Service explained some of those requirements in a report on shutdowns last month.

According to the analysis, agencies must submit summaries of activities that will continue and those that will cease during a shutdown, and they have to provide an estimate of the time to complete their closure plans, to the nearest half-day.

Agencies must also account for how many employees they have, as well as how many would be exempted from furloughs because their jobs are necessary for safeguarding human life and property or supporting the constitutional responsibilities of lawmakers and the president. Those workers are often referred to as “essential,” although that label is controversial within the federal workforce.

OMB requires executive agencies to break out non-furloughed employees into five categories:

* Those who are necessary to protect life and property.

* Those who are necessary to perform activities expressly authorized by law.

* Those who are necessary to perform activities implied by the law.

* Those who are necessary to carry out the president’s constitutional duties and powers.

* Those who are paid from funding outside of annual appropriations, such as fees that U.S. Citizenship and Immigration Services collects from individuals who request immigration services and benefits.

As for that last category, USCIS derives about 95 percent of its funding from fees. As such, the agency planned to furlough only 2 percent of its workforce during the last furlough scare in 2011.

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