To answer the issues (as I see them) in order It is a RIDDOR - someone was injured, in hospital etc so needs reporting. THEN you need to do a thorough investigation including the questions about stopping and how etc. and if they do/not cause injury. Hope this helps.

Katie, you’re in danger of getting responses on 2 different aspects; reporting for the injury and reporting for a dangerous occurrence (which is what your post seems to be about) On the injury front, there isn’t enough information to determine whether this is reportable or not. That ‘someone’ has gone to hospital does NOT in itself trigger a report; it would depend on whether this was an employee or someone ‘not at work’. If the latter it might be reportable, otherwise not unless the injury is over 7 days or specified. On the dangerous occurrence front I don’t think it falls under any of the reportable categories including those relating to lifting equipment. I aren’t a lift expert but my admittedly limited knowledge suggests that most (not all) work on the principle of a motor, cable drum etc. I would say that if the power fails then either the drum stops pretty quickly (a motor needs power to operate) and/or the drum brake fails to safe and is applied bringing the car to a stop pretty quickly. I could be wrong. Overall I would suggest that it isn’t reportable as a DO but that doesn’t stop you making enquiries with our lift maintenance company with regards to your concerns.