Critical Limit in HACCP: Definition & Examples

Critical Limit

74°C. For cooked poultry, that number is the line between dinner and a deviation. Not 73.5, not “about 74” — the critical limit is the sharpest number in food safety, and it has to be exactly right.

Definition

A critical limit is the maximum or minimum value of a measurable parameter at a CCP that separates acceptable from unacceptable. Cross it, and the product is no longer considered safe — corrective action starts, no discretion.

Key facts

• Critical limits must be measurable in real time: temperature, time, pH, aw, chlorine concentration, metal detector sensitivity. “Looks done” is not a critical limit.
• They have to be scientifically defensible. The 74°C poultry standard rests on thermal-death data for Salmonella — you can’t just pick a number that feels safe.
• The operating limit is the buffer: aim for 76°C internally so normal wobble never touches the 74°C line. Breach the operating limit and you adjust; breach the critical limit and you hold product.
• Where do limits come from? Regulations (21 CFR 113 for canned foods), published science, challenge studies, and expert guidance from bodies like NACMCF and ICMSF.

Why it matters

Critical limits go wrong in two directions: set without science (“we’ve always used 70°C”), or set so tight the plant lives in permanent deviation. Both are failures. A validated limit, monitored in real time by someone with the authority to stop the line, is the single most powerful control in the factory. Everything else in HACCP is scaffolding around these numbers — get them right.

Sources: Codex CXC 1-1969; FDA.

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