Integration Time for RMS Meter Type

[EdgarRothermich]

Does anyone know the integration time of the RMS Meter in Pro Tools?

I think the Dorrough Meters are about 600ms and Plugins sometimes let you adjust the RMS Window. For example the dpMeter.
The Meter Preferences in Pro Tools let you configure all kinds of parameters for the various Meter Type, but the Integration Time parameter for the RMS Meter Type is grayed out. So it means it it fixed, but to what value?

This is the text from the user guide: It mentioned "range of time", but doesn't say how many ms.
RMS: Provides metering ballistics that display the average loudness (Root Mean Square of the signal) over a range of time. Peak metering, on the other hand, displays the peak signal level at any given point in time.