The maximum instantaneous rate of change of the magnetic field reached during each pulse. It's the single sharpest moment within the pulse shape, expressed in Gauss per microsecond (G/µs). Because the induced electric field in tissue tracks how fast the field changes rather than its static strength, Peak dB/dt is the most direct per-pulse measure of the induced stimulus. It's also the parameter that regulatory limits for induced-field safety (IEC 60601-2-33, ICNIRP) are defined against. Physically it's the same quantity as Slew Rate during the rising edge, but framed as an instantaneous exposure value rather than an engineering performance number.
dB/dt is how fast the magnetic field changes: the change in field strength divided by the time it takes, which is the steepness of the field-versus-time line. A steeper edge means a larger dB/dt. Because the body responds to a changing field rather than a steady one, dB/dt drives the stimulus; the single steepest point in a pulse is the Peak dB/dt.
