When a recall is announced, the number attached to it does most of the work in telling you how worried to be. But the classes are defined in regulation, not in plain language, and the definitions are narrower than people assume.

Class I: serious injury or death is reasonably probable

The regulatory language is specific: a situation in which there is a reasonable probability that use of, or exposure to, the product will cause serious adverse health consequences or death.

Two words carry the weight. Reasonable probability is a lower bar than certainty but a much higher one than theoretical possibility. And serious means hospitalization, lasting harm or death, not discomfort.

In practice, Class I food recalls cluster around a short list: Listeria monocytogenes, which can be fatal to pregnant people, newborns, older adults and anyone immunocompromised; E. coli O157:H7, which can cause kidney failure in children; Salmonella; botulinum toxin; and undeclared major allergens, which are Class I because for a genuinely allergic person the reaction can be anaphylactic.

That last category surprises people. A mislabelled cookie sounds trivial. For someone with a peanut allergy it is the same hazard as a pathogen, and the regulation treats it that way.

What to do: stop using the product now. Do not finish it, do not cook it hotter, do not give it away. Follow the remedy in the notice.

Class II: temporary or reversible harm

Use may cause temporary or medically reversible adverse health consequences, or the probability of serious consequences is remote.

This is the broadest and least intuitive tier. It covers things that will make some people unwell without lasting damage, and things that could be serious but almost certainly will not be — a contaminant at a level below the usual threshold of harm, say, or a drug slightly outside potency specification.

Class II deserves attention without alarm. Stop using the product, follow the remedy, and if you have already consumed it, you are probably fine but worth watching.

Class III: unlikely to cause harm

Use is not likely to cause adverse health consequences. Typically a labelling deviation, a packaging defect or a product that fails a standard without presenting a health risk — a net weight understatement, a missing nutrition panel.

Class III recalls are regulatory housekeeping. They exist because the rules require accuracy, not because anyone is in danger.

The two agencies that do not use classes

CPSC publishes hazards, not tiers

The Consumer Product Safety Commission describes what can go wrong — "fall hazard", "fire hazard", "laceration hazard" — and reports known incidents and injuries. There is no Class I equivalent.

So you have to read the hazard language, and the incident count tells you a great deal. A recall citing one reported incident and no injuries is a different thing from one citing forty incidents and twelve injuries, even though both are simply "recalls".

NHTSA issues campaigns, with two warnings that matter

Vehicle recalls are safety recall campaigns, each with a number. Most say to schedule a free repair at a dealership at your convenience.

Two phrases override that. "Do not drive" means the defect is dangerous enough that NHTSA is telling you to stop using the vehicle entirely — have it towed. "Park outside" means a fire risk serious enough that the vehicle should not be parked in a garage or near a structure, including while it is switched off.

These are the two phrases in all of US recall practice that most directly ask you to change your behaviour today. If a vehicle notice carries either, treat it as you would a Class I food recall.

Reading a recall that has no class

Classification happens after the recall is announced. FDA assigns a class once its health hazard evaluation is complete, which can take days or weeks. A recall can be public and unclassified for a while.

Unclassified does not mean mild. It means not yet evaluated. Read the hazard description and act on that.

Why this site shows both

We maintain an internal severity tier so that records from four incompatible systems can be sorted together. That tier is a sorting tool. Every record also shows the issuing agency's own classification, and where the two differ the agency governs. The methodology page documents exactly how the mapping works, including which parts are inference.

General information, not legal, medical or safety advice. Always follow the instructions in the official agency notice, which is linked from every record on this site.