PC vs PLC safety systems

For the past 12 years I have built, debugged and installed PC and Adept based automation systems. Our standard safety system went like this. An E-Stop would kill power and air and you would have to restart the process afterwards. To access the inside of the cell for error recovery and parts replenishment the tech would have a door override key. Normally if the door was opened the robot would servo out, conveyors will stop and the air would dump. To enter for error recovery (part fell off a pallet lets say) the key would be used. With the key on all tooling would stop and unless you stopped the robot from the monitor it would go to speed 20. In my experience there are many reasons for a tech or engineer to enter a cell and not have everything shut down. My question is in the PLC world what would be a "Standard" way of handling error recovery, parts replenishment, teaching points, accessing the inside etc.... Being new to PLC's and trying to learn programming I don't want to reinvent the wheel or waste time trying to do the impossible. I'm not looking for exact code but the process for handling these situations. I'm learning alot from you guys and I appreciate it.

Thanks Again

Jim

Emergency stop stops everything as soon as possible.
Safety door ( for normal operation as add paper to printer ) is
diffrent. Protocol:
- Operator 'knoks' by some pushButton when likes go in.
- everything inside the door goes to safety plase or do last task
ready and stops
- when nothing is moving, put pneumatic pressure for safety
pressure (for holding something but cannot hurt peoples) or off.
- open door solenoid an operator can go inside
- when operator goes out, operator closes door and confirm it by PB.
Process can Continue..
PC or PLC no difference ?