Preventive Controls Management and Monitoring
Domain 3 examines 117.135–117.145: how preventive controls are written, monitored, and recorded. The exam tests whether your monitoring design is specific enough that another trained operator could execute it identically.
What monitoring means
Monitoring is a planned sequence of observations or measurements that shows a preventive control is operating as intended. For each control the plan must state the parameter and the value it must meet, the method, the frequency, and who performs it. Part 117 uses "parameters and values" - minimum cook temperature, maximum line speed, sanitizer concentration. "Critical limit" is HACCP vocabulary; the concept aligns, the words do not.
Frequency and design
- Frequency must be enough to catch a loss of control before affected product ships; justify it by how fast the parameter can drift.
- Continuous monitoring (a recording thermometer on a fryer) still needs documented record verification at defined intervals.
- Allergen controls may be monitored by label reconciliation and changeover checks; sanitation controls by sanitizer concentration and cleaning verification.
- Records must show the actual observation, the time, and the initials, and must be reviewed within 7 working days by a qualified individual.
- Monitoring must be done by competent personnel, and that competence must be documented.
Worked example
A roaster runs continuous nut roasting at a minimum of 143 °C, checked every 30 minutes by the operator and cross-checked with a hand-held probe against the chart recorder. Why 30 minutes? Validation showed the roaster cannot drop more than 5 °C in 45 minutes, so the 30-minute check plus the continuous chart keeps product inside validated limits. At the 14:00 check the reading is 138 °C. The operator stops the line, holds product back to the last documented chart reading within limits, and records the deviation with time and initials. Monitoring design, not improvisation, is what limits the size of the affected lot.
Traps
- Recording "OK" or "pass" instead of the measured value.
- Setting a frequency with no rationale, or writing "as needed".
- Treating record review as monitoring - review is a verification activity.
- Monitoring the corrective action's completion instead of the control itself.
- Omitting the responsible position from the monitoring description.