personnel files are for all records relating to an employee's employment
Texas employers are not legally required to let employees view the contents of the personnel file
exception: public employees may request copies of their personnel file documents under the Public Information Act
only one separate file must be maintained apart from regular personnel records: medical information (including FMLA and workers' compensation records) - that is because the Americans with Disabilities Act requires that any medical records pertaining to employees be kept in separate confidential medical files
still, it is a good idea to maintain other types of records in separate files as well:
safety records
develop a secure file access procedure to ensure that only those who need to see certain records can ever see them
For an example of a personnel files policy, click here.