Dear Partho,
I believe 2 years back there was a big explosion in IDL chemicals at Hyderabad and two people died some were injured, on investigation it was noticed that the explosion was due to cell phone.
With this context would like to communicate to you is there is lot problem with the cell phone hence better to avoid usage of cell phones at work place.
This should be irrespective of the position and gender, you should provide mobiles for the employees in critical postions and also specifically ask them to restrict the cell phone usage to their respective cabins / admn office.
You should also specify in your policy that the mobile other than company provided will be seized by the security at the gate and beyond security gate don't allow any un-official mobile, the same is applicable to the visitors also.
The employees who are in postion of company mobiles should also not to use the mobiles at prodcution area / work places, if found discontinue the facility.
Some of the exemptions that need to be done are in emergencies ie., some employees family members are hospitalized etc then they have to obtain an approval from the HR head and carry the mobiles in side but the usage should be in their boss cabin or administrative area only.
The visitors may create issue,saying that their cell phone are used by security or some body else and got damaged in this cotext you should have a provsion for storing at security, pegion racks with lock and key ( specifically with two keys ) required.
In your policy you should also spell out the disciplinery actions you are going to take on the employees who violates the instructions and display a notice on the same giving a 15 days advance notice and implement.
As I was with a chemical plant, we have implemented this system, there was lot of resistance, to avoid usage of company phones in the absence of mobiles we have provided two coin phones also.
With best regards - kameswarao