Requirements for Critical Unit Processes


Critical process parameters (CPPs) can be identified through the use of hazard analysis and critical control points (HACCP) analysis. HACCP is a process control system designed to identify and to prevent microbial, chemical, and physical hazards in production. It includes steps designed to prevent problems before they occur and to correct deviations as soon as they are detected. Such preventive control systems with documentation and verification are widely recognized by scientific authorities and international organizations as the most effective approach available for producing products safely. HACCP consists of seven principles: hazard analysis, critical control point identification, establishment of critical limits, monitoring procedures, corrective actions, record keeping, and verification procedures.

Hazard Analysis

Plants determine the food safety hazards and identify the preventive measures the plant can apply to control these hazards.

Critical Control Point Identification

A critical control point (CCP) is a point, step, or procedure in a food process at which control can be applied and, as a result, a food safety hazard can be prevented, eliminated, or reduced to an acceptable level. A food safety hazard is any biologic, chemical, or physical property that may cause a food to be unsafe for human consumption.

Establishment of Critical Limits

It is important to establish critical limits for each critical control point. A critical limit is the maximum or minimum value to which a physical, biological, or chemical hazard must be controlled at a critical control point to prevent, eliminate, or reduce it to an acceptable level.

Monitoring Procedures

Monitoring activities are necessary to ensure that the process is under control at each critical control point.

Corrective Actions

Corrective actions are to be taken when monitoring indicates a deviation from an established critical limit. The final rule requires a plant’s HACCP plan to identify the corrective actions to be taken if a critical limit is not met. Corrective actions are intended to ensure that no product injurious to health or otherwise adulterated as a result of the deviation enters commerce.

Record Keeping

HACCP regulation requires that all plants maintain certain documents, including its hazard analysis and written HACCP plan, and records documenting the monitoring of critical control points, critical limits, verification activities, and the handling of processing deviations.

Verification Procedures

Procedures for verifying that the HACCP system is working as intended are required. Validation ensures that the plans do what they were designed to do, that is, they are successful in ensuring the production of safe product. Verification ensures that the HACCP plan is adequate, that is, working as intended. Verification procedures may include such activities as review of HACCP plans, CCP records, and critical limits, and microbial sampling and analysis.


The production of safe products requires that the HACCP system be built upon a solid foundation of prerequisite programs. This process traditionally has been accomplished through the application of good manufacturing practices (GMP). These conditions and practices are now considered to be prerequisite to the development and implementation of effective HACCP plans. Prerequisite programs provide the basic environmental and operating conditions that are necessary for the production of safe products. Common prerequisite programs may include, but are not limited to:

Facilities. The establishment should be located, constructed, and maintained according to sanitary design principles. Linear product flow and traffic control minimize cross-contamination.

Supplier control. Each facility should ensure that its suppliers have in place effective GMP and safety programs. These may be the subject of continuing supplier guarantee and supplier HACCP system verification.

Specifications. Written specifications for all components, products, and packaging materials are needed.

Production equipment. All equipment should be constructed and installed according to sanitary design principles. Preventive maintenance and calibration schedules should be established and documented.

Cleaning and sanitation. All procedures for cleaning and sanitation of the

equipment and the facility should be written and followed. A master sanitation schedule should be in place.

Personal hygiene. All employees and other persons who enter the manufacturing plant should follow the requirements for personal hygiene.

Training. All employees should receive documented training in personal hygiene, GMP, cleaning and sanitation procedures, personal safety, and their role in the HACCP program.

Chemical control. Documented procedures must be in place to ensure the segregation and proper use of chemicals in the plant. These include cleaning chemicals, fumigants, and pesticides or baits used in or around the plant.

Receiving, storage, and shipping. All raw materials and products should be stored under sanitary conditions and the proper environmental conditions, such as temperature and humidity, to assure their safety.

Traceability and recall. All raw materials and products should be lot-coded and a recall system in place so that rapid and complete traces and recalls can be done when a product retrieval is necessary.

Pest control. Effective pest control programs should be in place.

Other examples of prerequisite programs might include quality assurance (QA) procedures, standard operating procedures (SOPs) for sanitation, processes, and product formulations, glass control, procedures for receiving, storage, and shipping, labeling, and ingredient handling practices. Figures 46.1 and 46.2 can be used to determine whether a process parameter is a CCP.