Hello Stressers!!!

I have come along these two units for Vibration Amplitudes vs. Frequency (Hz) to categorize severity of vibration.

Basically, in EI guideline the unit given is Vibration Amplitude (RMS velocity) (mm/s) but in EDI article the unit given is Vibration amplitude (mils p-p).

What's the difference between the two?

Many Thanks in Advance.

Cheers...