Principle 3

Critical limits must be specified and validated for each CCP. In some cases more than one critical limit will be elaborated at a particular step. Criteria often used include measurements of temperature, time, moisture level, pH, Aw, available chlorine, and sensory parameters such as visual appearance and texture.

Critical limits should be measurable, scientifically supported, and able to differentiate safe from unsafe product. Where critical limits are based on subjective data (e.g. visual inspection), they should be supported by instructions, specifications and/or training.