Fuel unloading from Bushehr reactor is “a necessary precaution”, the State Atomic Energy Corporation ROSATOM states. “Damages to internal elements were revealed in one of four cooldown pumps at Bushehr NPP. In this regard an assumption has come up that metal particles (predominantly chips of less than 3 mm) could get together with water into the reactor pressure vessel (RPV) and, having passed though the reactor internals, to get onto fuel assemblies,” a Rosatom’s statement of February 28 says.
Source: Nuclear.Ru