All, Due to continued cleanliness and safety issues with the hoods both in the cleanroom and general laboratories the following procedure is to be implemented immediately. Before using any fume hood in Birck the user must sign into the log posted on the fume hood and upon completion of use of the hood sign out. Failure to do so will result In laboratory access being suspended. This procedural requirement is effective as of 4/17/17. Stephen Jurss Birck nanotechnology Safety Officer