Recently there was a large rat nest discovered and removed on the B-loading dock of CHS. Shortly thereafter a rat was observed coming out of a biohazard container in the medical waste accumulation site at the CHS B-loading dock. The rat was attempting to enter a biohazard bag that contained used rodent cages but only managed to breach the outer bag. Biosafety noticed the rat was able to enter the waste barrel because the locking mechanism of the lid was broken. Upon further inspection many of the lids had broken locking mechanisms. Our medical waste vendor Stericycle responded quickly and replaced all of the broken lids on campus. Nevertheless, we ask that you inspect the locking mechanism on each lid handle and ensure that both are intact before you place the lid atop the barrel. Stericycle has recommended that when attaching the lid to a barrel to firmly press each handle down while pulling the outer section of the handle up. Please DO NOT slam the lids onto the top of the barrels as this can result in breaking of the locking mechanisms. Finally, if you do notice a broken lid please set it aside for the vendor to pick up. If you have any questions, concerns, or comments about this please reach out to Biosafety ([email protected]edu) or (310) 206-3929.