In the field of food safety systems multiple standards are available to use. The standards show lots of similar aspects (the main objective of course is the same) but the content of specific requirements and the structure of the standards differ. Some standards (like the FS 22000) consist of general requiemetns and some standards show specific requirements in the format of a checklist.
The FS 22000 is a general standard for food safety systems. It resembles the ISO 22000 but has one specific difference. It includes the pre requisite requirements as published in the PAS 220. The FS 22000 is accepted by the GFSI.