I am looking for a procedure to help better manage changes made to PLCs in a manufacturing facility. As you know, changes made to PLCs fall into several categories. Some changes impact validation, while others are normal production activities. The validations department at my company cannot handle review of every single change made to the PLC. What guidelines could we put in place to ensure that appropriate changes get reviewed by validation, without having to review normal production changes (e.g. configuration, addition of an employee, etc) I would imagine that company policies would break down changes into varoius categories and specify the requirements for each category type. But, I can't seem to find any examples of what these categories/requirements would be. Any suggestions?