# Vibration Case Studies > < [[Environmental Conditions MOC]] ## pump interferes with surgical microscope https://www.mcsal.com/services/vibration-consulting/sensitive-equipment/ A surgical microscope was being disrupted by excessive vibrations #### RESULTS The largest vibration levels measured at the microscope eye were around 21 Hz. Disruptive vibration levels were observed only when the motor of a condenser water pump operated at 1,260 RPM on the mechanical floor. #### **SOLUTION** The pump controller was reprogrammed to skip the frequencies near 21 Hz which eliminated the resonance problem, hence, the vibration issue was solved with minimal cost. ## Laboratory floor ambient vibration analysis [[W204 - Evaluation of site vibrations for AUV laboratory according to vibration criteria.pdf]] ![[Screen Shot 2022-01-28 at 11.26.33 AM.jpg]] ## via listserv > Vibrations can be very vexing to deal with so let me share three experiences I have had over the years. Possibly these adventures will present some new ideas in your search. > >> A microscope in Milwaukee had an intermittent, low frequency vibration problem and after a couple days, I traced it to a very long air conditioning duct located in the attic of the hospital. The duct was acting like a low frequency organ pipe and was actually shaking the building structure. Solution: Three or four holes were punched in the pipe to detune it thereby altering the resonant frequency. The air conditioning flow was still acceptable and the vibration was gone. > > > Another interesting problem presented itself in Miami, Florida. At about the same time every day, it was impossible to do any usable microscopy because of some mysterious vibration. Why was it always at the same time? A golf course a couple blocks away turned on its sprinklers every day at the same time and their pumps vibrated the ground enough to mess up the microscope resolution. > > > Finally, I was chasing a very low frequency vibration at the Mayo Clinic and since my vibration equipment was portable, I went outside the lab and took a tour of the beautiful campus. Fortunately, it was in the summer. Anyway, the vibration seemed to indicate some sort of rotating source. I ended up at an auxiliary power generating facility, watched my equipment for a while and decided one of the generators located inside had a bad bearing of its drive shaft. I went in and told a guy who seemed in charge that he had a bad bearing on one of his dynamos. He said, "you're right. How did you know that? We are waiting for replacement parts." Magic, I said. > Good luck, Alex Greene - Scientific Instrumentation Services, Inc.