Anyone whose work involves lifting, carrying or otherwise handling a load, including where a mechanical aid is available but the handling has not yet been avoided, assessed or reduced.

Manual handling injury is one of the largest causes of lost working days, and a lifting technique course on its own does not discharge the employer's duty to avoid, assess and reduce the risk.
The pack works through avoiding the handling where possible, a TILE assessment of the task, individual, load and environment recorded on a real task, safe lifting technique including moving the feet to turn rather than twisting the spine, team lifts, and when to stop and ask for help: a load heavier than expected, a blocked route, or any pain or strain.
One hazard, done completely, for the whole firm.
The pack also has a theory test answer key. It is supplied separately to the employer, not published in the pack itself, so the test stays a genuine assessment when your own supervisor marks it.
Not required to be compliant, but available where a customer, principal contractor or insurer wants third-party evidence.
You assess your own people in-house using the pack, and send PHW the completed records. PHW checks the records and, where they hold up, issues a certificate carrying a QR code that resolves to a live verification page. The certificate states plainly that the assessment was carried out in-house and verified by PHW. It is not a record of PHW having carried out the assessment itself, and records that are too thin are rejected rather than certified.