The union say sub-standard conditions for outpatients Water Reed hospital were caused by the privatization of maintenance there.

"What happened at Walter Reed is all-too-typical of the results of federal contracting (out)," said Colleen Kelley, president of the National Treasury Employees Union in a statement this week.

The union called the scandal over conditions at the hospital "a not-at-all surprising result of a federal contracting process that drives experienced federal employees from their jobs and seeks to replace them with unaccountable private contractors."

In the wake of the Walter Reed revelations, Sen. Barbara Mikulski, D-Md., noted that when the hospital first began gearing up to a privatize maintenance work, more than 300 employees were doing it. By last month, when the private contractor took over the work, fewer than 60 remained.