Department policy: "Every self-contained breathing apparatus (SCBA) must be inspected at the start of each shift. The inspection includes checking the cylinder pressure gauge, testing the low-air alarm, and confirming the face-piece straps are fully loosened. Any SCBA with a cylinder below 90 percent of full pressure must be removed from service and replaced." According to the passage, an SCBA must be removed from service when the cylinder pressure is: