Does ultrasonic bath cleaning damage laboratory volumetric glassware calibration?
According to technical information for volumetric measurement provided by Brand, it is acceptable to use an ultrasonic bath.


  Both glass and plastic labware may be cleaned in an ultrasonic bath. However, direct contact with the sonic membranes must be avoided.


Nevertheless,


  For gentle treatment of labware, clean immediately after use – at low temperatures, with brief soaking times, and at low alkalinity. Glass volumetric instruments should not be exposed to prolonged immersion times in alkaline media above 70 °C, as such treatment causes volume changes through glass corrosion, and destruction of graduations.