1.  I don't see how HSE could include this in their stats as they don't collect the data.

2(a). Regulation 14 of RIDDOR specifically excludes most road injuries and deaths from scope.  HSE is not the regulator for road safety; instead it's a police matter.

2(b). There is no legal requirement for an employer to investigate any work-related injury or death.  Investigation falls in the realm of good practice.

Hi Argyll

The exclusion from scope of most work-related transportation accidents (that would otherwise be reportable or recordable) in RIDDOR has long been a subject of debate with calls for change from e.g. RoSPA.

Perhaps not quite so pertinent post Brexit, but EU Member States are required to provide statistical information to Eurostat to help establish benchmarks, with the criteria being broadly similar to those in RIDDOR.

This has meant that HSE has had to guestimate how many road traffic accidents should be included in date provided to Eurostat.

Which has been problematic as there is nothing like a consensus as to how many road traffic accidents in the UK are work-related.

At one point, HSE guessed 10%, RoSPA (who probably know more about the subject than HSE) went for 25% whilst Devon and Cornwall Police reckoned it was about 40% in their part of the country.

As for your question about whether employers have to investigate accidents etc,, I think it's an implicit requirement of Regulation 3 of the Management of Health and Safety at Work Regulations 1999.

(3) Any assessment such as is referred to in paragraph (1) or (2) shall be reviewed by the employer or self-employed person who made it if—

(a) there is reason to suspect that it is no longer valid; or

(b) there has been a significant change in the matters to which it relates; and where as a result of any such review changes to an assessment are required, the employer or self-employed person concerned shall make them.

I can't see how the duty holder could possibly conclude that there is NOT a "reason to suspect" that their risk assessment "is no longer valid" UNLESS they do at least a cursory investigation when an unintended incident occurs.