This fan has been on continuously for the past several years.  I noticed that it is starting to get noisy - mostly due to an unexplained increase in flow.  Even at the minimal speed setting, the flow seems to be excessive for some reason.  This fan exhausts the area above VBOA in Room 169, as well as, the two air-bake ovens in the adjacent Vacuum Prep Lab -> I will add signage to the air bake ovens so as to notify would be users that the exhaust is off and describe the details for turning it back on.