RIDDOR, explained: what has to be reported to the HSE, and when

The Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013 (RIDDOR) require certain workplace incidents to be reported to the HSE — specified injuries, certain occupational diseases, and defined dangerous occurrences, each with its own reporting category and timeframe.

What's actually reportable

Broadly, this covers: deaths and specified serious injuries (reportable without delay), injuries causing more than a set number of consecutive days off normal work, certain occupational diseases, and dangerous occurrences — incidents that didn't cause injury but easily could have, such as certain scaffold or plant failures. It's worth being aware that some of these thresholds are currently under review — see what's proposed to change in 2026.

The four categories, unpacked

• –Deaths and specified injuries — the most serious category, generally reportable without delay, covering fatalities and injuries HSE classes as specified (fractures other than to fingers or toes, amputations, and similar)
• –Over-incapacitation injuries — injuries that keep someone off their normal work, or unable to do it fully, for more than the current specified number of consecutive days
• –Occupational diseases — certain diagnosed conditions linked to the work being carried out, reported when a doctor's diagnosis confirms the link
• –Dangerous occurrences — specified near-miss-type events that didn't cause injury but had clear potential to, such as certain collapses, failures of lifting equipment, or uncontrolled releases

Timeframes that actually matter

The most serious category has to be reported without delay — which in practice means as soon as reasonably possible, not at the end of the working day once things have calmed down. Other categories generally allow a short reporting window, but the discipline that matters on site is capturing the facts accurately at the time, since the report itself is often written up after the immediate response to the incident, when memory of exact circumstances has already started to fade.

A worked example

Someone falls from a low platform and fractures a wrist. Is that a specified injury or an over-incapacitation injury? It depends on the exact nature of the fracture and how HSE's current categories classify it — which is precisely the kind of judgement that shouldn't be made from memory of a general rule of thumb. The safer approach on site is to have whoever's responsible for incident reporting check the injury against HSE's current guidance directly at the time, rather than guessing based on how a similar-sounding injury was handled on a previous project.

Where the judgement calls actually happen

The clearest cases — a fatality, a major injury — rarely cause confusion. The harder judgement sits with incidents that are serious but ambiguous against the reportable categories, and with near misses that didn't meet the RIDDOR threshold but are still worth recording internally regardless.

Who's actually responsible for reporting

The responsible person for RIDDOR purposes is generally the employer of the person who was injured, or the person in control of the premises where the incident happened — which on a construction site with multiple contractors working alongside each other can genuinely need thinking through rather than assuming. If a subcontractor's employee is injured while working on a principal contractor's site, it's worth both parties being clear in advance about who's actually submitting the report, rather than each assuming the other has it covered and the report never being made at all. This is exactly the kind of gap that's easy to create when duty-holder roles aren't clearly established, which connects back to getting CDM 2015 roles right from the outset.

Reporting versus recording — a distinction worth keeping straight

Not every workplace injury needs reporting to HSE, but most workplaces are still expected to keep an internal record of accidents that happened, even the ones that don't meet the reportable threshold. Confusing "this doesn't need reporting to HSE" with "this doesn't need recording at all" is a common and costly mistake — an internal accident record that only contains RIDDOR-reportable events is missing the pattern of smaller incidents that often precedes a serious one, in much the same way that ignoring near misses means missing an early warning.

What happens after a report is submitted

Submitting the report isn't necessarily the end of the process. HSE may follow up depending on the nature and severity of the incident, and it's worth being prepared to provide further detail if asked — which is another reason the initial record needs to be accurate and specific, not a rushed summary written to get the notification done. Keeping supporting evidence from around the time of the incident — inspection records, RAMS in force at the time, photographs if relevant — alongside the RIDDOR report itself means that if a follow-up query does come, the answer is a matter of retrieving existing records rather than reconstructing events from memory.

Common mistakes

• –Under-reporting because an injury "didn't seem that serious at the time," before the full extent was known
• –Delaying a report while waiting for complete details, rather than reporting promptly and updating the record as more information comes in
• –Not keeping a clear internal record of incidents that fell just short of the reportable threshold
• –Relying on how a similar incident was categorised on a past project instead of checking the injury against current HSE guidance
• –Treating RIDDOR reporting and internal inspection and incident records as separate exercises, when the detail in one often depends on the other
• –Assuming the other party on a multi-contractor site has already reported an incident, when neither party actually has

This post is a starting orientation, not the statutory list itself — check current HSE guidance directly, particularly given RIDDOR is under active consultation at the time of writing.