Turnaround can also be used as a synonym of shutdowns and outages. This usually is a significant problem due to unplanned shutdowns. Many shutdowns and job losses have plagued Gastonia over the past decade. Instances of power grid shutdowns caused by squirrels have been tabulated. Seventy percent of DHS employees are considered essential and are not furloughed during government shutdowns. The reactor normally operated around the clock, with 10-hour weekly shutdowns for refueling. A widespread programme of reactor checks was started involving a progressive programme of reactor shutdowns. Gingrich furthermore oversaw several major government shutdowns. Following numerous script revisions and two production shutdowns, the series was canceled. The Park has been subject to frequent shutdowns due to political tensions. Safety meetings are typically held before and during shutdowns. Gingrich was also involved in several major government shutdowns. Cyclic catalytic reformers serve to extend the period between required shutdowns. Since 2015, there have been three blizzard-related subway shutdowns. The labor cost for this role is significantly lower than costs involved with production shutdowns.