AK - I think the overall approach is broadly similar in HSE as it is in ORR not least given the number of staff that ORR inherited from HSE when there was a recognition that it would be helpful to abandon the prescription that HM Inspectors of Railways should necessarily come from a background in the rail sector - and hence bring in some fresh thinking.
But also if you compare the training of new Inspectors:
So HSE:
A requirement for all new General and Regulatory Specialist Inspectors is to obtain a Post-Graduate Diploma in Regulatory Occupational Health and Safety which is bespoke to HSE (accredited by NEBOSH). This will give you the technical and legal skills you need to do your job as an effective regulator, under-pinned by an academic qualification. This is a valuable opportunity to obtain a qualification from one of the UK’s best regarded vocational awarding bodies, funded by your employer. All newly appointed Regulatory Trainee Inspectors will undertake the Diploma which can take up to 3 years to complete. Following completion of the Diploma, a year of mandatory Continuing Professionally Development (CPD) will be required. [My italics]
....and ORR:
ORR delivers a three-year structured training programme to enable trainee inspectors to demonstrate initial competence. Training is coordinated by ORR’s Learning and Development team. On successful completion of the training programme, you will be awarded a Diploma in Regulatory Railway Health and Safety, accredited by NEBOSH, which is an externally recognised qualification. [My italics]
So the days of being sent away to Imperial College or Aston Uni for 6 months to get a Post Grad Diploma as part of a two year HSE training programme have gone to be replaced by a NEBOSH Diploma in "Regulatory Health and Safety" [+ in each case a single word to distinguish an HSE Inspector Diploma from an ORR one]. In practice the overall training period was of similar duration - 2 years, then another as a qualified Inspector before promotion to the next grade.
It is difficult to see how the content of these "different" NEBOSH Diplomas might not be largely identical since what the Inspectors do in two Regulators is broadly the same.
Enforcement of the Health and Safety at Work etc Act and whatever subordinate legislation applies to the sector or sectors the Inspector is working in.
So the HSE Inspector does not need to learn about rail specific legislation, but needs to learn about comparable requirements in e.g. COMAH - though perhaps not as immediately..
Similarly the ORR Inspector wouldn't need quite as much understanding of CDM as the inspection of most major construction projects on the rail network falls to HSE.
But beyond those differences, each Inspector has essentially exactly the same legislation to enforce and, thence, needs broadly the same skill sets except that the ORR Inspector is less likely to face abuse when visiting e.g. scrap merchants and back street garages - but then I don't remember the syllabus when I went to Aston covering that particular challenge!!