Does anyone know how micro film is to be stored? Does it need to be locked up and if so does it need to be in a fire proof cabinet?

Depends on what documents are on the film. Some only need to be kept 3 years, some 7 years, some 10, and some indefinitely.
For example, personnel records only need to be kept for 3 years after the employee left the company. Payment check film, is 7 years, and so on.

We store the most recent 12 months on site with a copy at a second location. All else goes into a long term storage facility. (3rd party vendor)

You should duplicate your film and keep one to use and one either off-site or in a fireproof vault. The retention of the film is the same as the paper document. You should film documents with the same retention periods together so you will be able to destroy the film when the time is up.

micro film.... what's that?

Microfilm is an filmed image that is produced with a microfilm camera.

That is the stone age version of imaging!

In terms of how microfilm should be stored...It should be in a humidity/temperature controled environment. Temp/humidity should not vary more that 5 degrees or 5% in a 24 hour period. Separate your original film (probably silver halide) from your diazo (occasionally duplicate film is amonia processed). The amonia fumes can damage the silver halide and cause it to have blemishes ("redox" or measles). Temperature should be around 65% and humidity around 40%.