Mechanical Vibration

Amplitude - mm , μ (depending on your equipment and its speed)

Velocity - mm/s, μ/s

Acceleration - mm/s², μ/s²

The requirements (limits) are defined in various standards, some detailed standards are there in VDI.

Though these are for general equipment categories, and in specific machines, one may have to define the limits.

The Mech Engineers I've worked with use huge shaker tables to test electronic assemblies. The shaker tables can provide a wide range of signals and intensities, such as a sine input, a random input, or a shock input. In general, though, the strengths are measured in term of 'g', where 1 g is 9.8 m/s².

Here's a link to one company, with a handbook you can download.

http://www.thermotron.com/products/vibration.html