As a general rule, the following physical points should be kept in mind when dealing with mechanical equipment:
• Apply lubrication (a badly lubricated mechanism will not only squeal, but it will also wear out more quickly).
• Most of the time speed means noise (slower equipment will usually be quieter than faster equipment): Try to opt for equipment with reduced speed.
• Provide adequate ventilation to the equipment (A badly ventilated equipment will not only have whining fans but also overheat).
• Make sure the section of the ventilation ducts is large enough (if it is not, the speed will be too high and there will be noise generation).
• Provide resilient supports under the equipment to keep vibrations from spreading around.
• Provide acoustic absorption close to the equipment (just imagine the acoustic energy radiated from the equipment and try to intercept it).
• Make sure there is easy access for maintenance purposes (badly maintained equipment will be noisier than properly maintained equipment); more to the point, if there are noise control elements such as an enclosure to be dismantled prior to maintenance, you can bet it will not be properly reassembled later on).
• Try to find a location for the equipment that is close enough.