Prerequisite programs are steps or procedures, including GMPs and SSOPs, which control the operational conditions within a food establishment and promote environmental conditions that are favorable for the assembly of safe food. Prerequisite programs are the inspiration of a Food Safety/HACCP system. Consistent with Appendix K of the PMO, before the implementation of a Food Safety/HACCP plan, plants must develop, document, and implement written prerequisite programs.

ISO 22000 identifies areas and programs that has got to be considered during the event of PRPs. for instance, pest control programs, personnel hygiene and lay-out of premises. However the quality leaves the responsibility for developing the small print of the program to the organization; it doesn't give specific requirements for the pest control program, it ask you because the organization to work out what's appropriate for your organization.

To give companies additional guidance as they build prerequisite programs, ISO has published a technical specification, ISO/TS 22002-1 "Prerequisite programs on food safety-Part 1: food manufacturing". This document is like the PAS 220, which has been withdrawn and replaced by the ISO Document. ISO/TS 22002-1 and is meant to be used with the ISO 22000 standard, and provides more detailed requirements for food manufacturers to follow when developing and implementing PRPs. Unlike ISO 22000, which applies to all or any organizations within the organic phenomenon, ISO 22002 applies only to Manufacturers of food.

Requirements of ISO 22002-1 and therefore the PAS 220

• Prerequisite programs in ISO 22002-1 (Previously the PAS 220) include requirements for:
• Construction and layout of building
• Layout of premises and workspace
• Utilities - air, water, energy
• Waste disposal
• Equipment suitability, cleaning and maintenance
• Management of purchased material
• Measures for prevention of cross contamination
• Cleaning and sanitizing
• Pest control
• Personnel hygiene and employee facilities
• Rework
• Product recall procedures
• Warehousing
• Product information
• Food defense, biovigilence and bioterrorism