What the law requires
Regulation (EU) 2017/2158 on acrylamide requires food businesses that fry French fries and other potato products and sell them in retail to use oils that allow quicker frying or lower temperatures, to keep frying temperatures below 175 °C, and to maintain oil quality by skimming off crumbs frequently (Annex II, Part A). The Commission Notice on food safety management systems (2022/C 355/01) gives checking the time and temperature of frying oil as an example of a critical control point. Neither Regulation (EU) 2017/2158 nor Regulation (EC) No 852/2004 sets a limit for oil quality or a rule for when to change the oil, so your own HACCP plan sets the limit and how often you check.
Write the limit for changing the oil from your HACCP plan at the top of the sheet. When you fry potato products such as French fries, keep the oil below 175 °C (Regulation (EU) 2017/2158).