In the implimentation of HACCP,
Prerequisite programmes (PRPs) – are the basic conditions and activities that are necessary to maintain a hygienic environment throughout the food chain. Basically, these are GMPs – Good Manufacturing Practices.
Operational prerequisite programme (OPRPs) – are PRPs that are identified by the hazard analysis as essential in order to control the likelihood of introducing food safety hazards to and the contamination or proliferation of food safety hazards in the product(s) or in the processing environment
Critical control point – step at which control can be applied and is essential to prevent or eliminate a food safety hazard
or reduce it to an acceptable level. Usually, hazards that are not controlled at the CCPs are controlled using the OPRPs.