Velocity and displacements From PSD Profile

I am wondering if anyone out there has an easy method of arriving at maximum velocities and displacements which will be seen when running a given PSD using a shaker.

I require this information so that I can quickly check that profiles supplied are within the capabilities of our test equipment.

For example what displacements and velocities would be seen when running:
Hz G^2/Hz
20 0.001
50 1.0
250 1.0
300 0.001

Thanks in advance for any help.