Only federal employees who are "necessary to protect life and property" and are needed to perform an "orderly shutdown of emergency operations" are considered "essential." That includes most national intelligence staff, military personnel, air traffic controllers, law enforcement, emergency and disaster personnel, the Transportation Security Administration, Coast Guard and similar staff.
Nonessential staff cannot report to work or use their computers while they are furloughed.
House Republicans are rallying behind a new temporary funding measure introduced Monday night that would keep the government running for another week while cutting $12 billion in discretionary spending. The move, they said, would keep the government's doors open as lawmakers hash out a long-term plan.
The legislation allocates $515.8 billion in base funding for the Department of Defense until September, a 1.5 percent increase from 2010. It cuts $2.5 billion from labor, health and human services; about $2 billion from transportation and housing programs; $1.4 billion from the Department of Homeland Security; $1.27 billion from the Interior department; $832 million from domestic and international operations; $632 million from the Energy department; $590 million from financial services programs and $430 million from accounts of the Commerce, Science and Justice departments.
Most Americans, far removed from the daily partisan grinds of Washington, are unlikely to experience a direct impact. But experts said a shutdown could damage the economy and consumer confidence if it is prolonged. It will also end up costing the government more, especially if furloughed employees have to be paid retroactively.
The U.S. Postal Service will operate as normal, since it is self-funded. Social Security, veterans and Medicare checks would continue to be disbursed, although there could be a delay in services for new registrants and those who have filed a change of address form.
Americans who receive food stamps also will continue to do so, but if the shutdown is prolonged, such disbursements are likely to be delayed and backlogged.
Many Americans may have to hold off on their travel plans. Museums and national parks will close, as will the national zoo, and passport applications are likely to be delayed.
Some government inspection services, such as for meat, may be delayed.
The uncertainty could also roil stock markets and rattle consumer confidence, though that would depend on how long a shutdown lasts. Lawmakers could use the weekend to cobble together a plan that would minimize the impact, since the federal government is shut over the weekend.
Members of Congress and their essential staff will continue to work and be paid. The Senate last month passed a bill calling for a freeze on lawmakers' paychecks in case of a government shutdown.
A similar clause was included in the Government Shutdown Prevention Act, which was passed by the House on Friday. But that legislation holds no chance of making it through the Senate, since it would make the House Republicans' budget bill for 2011 the law of the land if the Senate doesn't pass an appropriations bill.
Democrats are placing the blame squarely on the Tea Party for stalling negotiations. Several Tea Party members of Congress support a government shutdown if that's what it takes to stick to their desired cuts.