RIDDOR Explained: 4 Reporting Boundaries for UK Safety Teams

A reportable event can be legally significant without being the most useful description of the risk that produced it. RIDDOR helps UK employers notify certain work-related deaths, injuries, diseases and dangerous occurrences, but the notification itself does not demonstrate that the work system was under control.

RIDDOR, the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013, is the UK notification framework for specified work-related events. It tells an employer when information must be reported to the enforcing authority, while the investigation and control process must explain what happened, what could have happened, and what will prevent recurrence.

Definition

RIDDOR is a legal reporting boundary, not a complete incident-investigation method. The responsible person must assess whether an event falls within a reportable category and then meet the applicable reporting deadline. That decision should be based on the facts available, because a label chosen too early can narrow the investigation.

Andreza Araujo makes a related distinction in Sorte ou Capacidade, where legal compliance is treated as the floor rather than the ceiling. The same logic applies here. A notification may satisfy a duty while leaving the exposure, barrier weakness and management decision unexplained.

4 reporting boundaries that change the decision

1. Specified worker injury

Some serious injuries are reportable because the injury type or consequence meets the regulation's defined threshold. The practical question is not only whether the person was hurt, but whether the medical facts and work connection place the event inside that boundary.

2. Over-seven-day absence

A worker injury that keeps the person away from normal work for more than seven consecutive days follows a different reporting boundary from a shorter absence. Preserve the timeline, medical information and work-status decision, because the reporting classification can change as recovery develops.

3. Occupational disease

RIDDOR also covers certain diagnosed diseases when work is a material cause and the relevant reporting conditions are met. This requires coordination between occupational health, HR and the operational manager, since a diagnosis can be missed when each function holds only part of the evidence and the work exposure is recorded in fragments across different systems that were never designed to speak to one another.

4. Dangerous occurrence

A dangerous occurrence is a specified high-potential event that may require reporting even when nobody is injured. That is why a near-miss signal review should not be confused with a legal notification. The first tests the strength of the warning; the second tests whether a defined reporting threshold was crossed.

How to differentiate the boundaries in practice

The strongest first response is an evidence-preservation routine that keeps the reporting decision and the control decision connected. For serious events, compare the notification record with the deeper incident-investigation method, because a legal form cannot replace barrier analysis, witness interviews or a review of organizational conditions.

When to use RIDDOR versus an internal review

Use RIDDOR when the event meets a specified legal boundary. Use an internal review whenever the event reveals a credible weakness, even if no notification is required. A team that investigates only reportable events will miss the smaller signals that show how exposure is becoming normal.

This is also where reporting culture matters. A worker who can raise a concern without retaliation gives the organization better evidence before harm occurs, which is why the practical ideas in psychological safety and honest reporting belong beside legal reporting guidance.

For UK teams, the useful test is simple but demanding. Ask whether the notification is accurate, whether the evidence is preserved, and whether the resulting action changes a control rather than merely adding another form. That is how a RIDDOR decision becomes part of safety management instead of a compliance endpoint.

Explore Andreza Araujo's safety leadership resources for further guidance on turning compliance evidence into safer work.