Risk assessment and frequency of replacement of Protective clothing

In the SPS Standard Version 6, Ready-to-Eat Module, item RTE11 states that:“Protective clothing shall be changed at a frequency based on risk assessment or at least once per shift.”

Could someone please share a reference table on PPE risk assessment and replacement frequency?

Additionally, I would like to clarify whether “at least once per shift” means once every 4-hour shift (after lunch break) or once every 8-hour working day?

A shift would normally be a working day.

Most ready to eat plants would have rules to change when visibly soiled or minimum once a day.  A standard risk assessment template would suffice.  You'd need to think about how soiled clothing gets in different areas and allergen and micro risk.  Areas in ready to eat factories which normally need more frequent changes tend to be where there is a lot of open product mixing unless it's very well controlled and also hygiene areas but that's more for staff comfort.