The Obama administration is circulating procedures for how the Department of Homeland Security will operate in the event of a midnight shutdown.

The 46-page document outlines what is exempt from the shutdown, including airport security checkpoints, Secret Service activities and border patrols. But employees involved in planning, auditing, training and other policy functions would be furloughed.

Employees who keep working during a shutdown would not be paid until Congress approves additional funding.

Hours before the midnight deadline, the Republican-controlled House unexpectedly rejected short-term funding for DHS. The vote's failure increases the prospect of a partial shutdown of an agency with major anti-terrorism responsibilities.