Page 23 - HydrophoneHandbook_eReader_Ed2_20151208
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Choosing a Hydrophone

In addition to mechanical damage from high acoustic pressure,
another mechanism that can damage the hydrophone is heat.
That is, some of the intensity of the ultrasound field can create
thermal damage to the hydrophone. In most cases, the pressure
considerations are the operative concern for hydrophone
measurements because pressure limits are reached before the
hydrophone can heat up due to the intensity, due to water
convection (Onda’s hydrophones are designed to measure only
in water). An exception is the HMB hydrophone, because its
rubber backing does not allow convective cooling. Therefore, it
is recommended to keep intensities below diagnostic
ultrasound levels of 720 mW/cm2.
Note also that each hydrophone data sheet has a maximum
temperature of water in which hydrophone can be submerged.

                  Measurable Pressure Range for Different Hydrophones

Hydrophone Model  HCT
                  HFO
                  HNA
                  HNR
                  HNC
                  HNP
                  HGL
                   HM

                  0.001          0.1 10                   1000

                         Measurable Pressure Range [MPa]

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