What must a security guard do when taking over a post?

Short answer

Report to the post before the shift starts, in uniform and with the equipment that post requires.
Take over the post through a handover report, signed together with the guard going off shift.
Check the post's equipment, radios and goods against the inventory list.
Read the post's specific standing orders and the events logged during the previous shift.
Confirm the handover to dispatch and report any missing item or fault on the spot.

Law 333/2003, art. 46 — while on duty a guard must know the vulnerable points inside the site (a), guard the goods listed in the security plan (b) and follow the post's standing orders (q).
Law 333/2003, art. 46 (e) — any event during the shift must be reported immediately to the direct supervisor and to the guarded company's management.
Standing orders come in two parts: the general ones, shared by every post, and the particular ones, taken from the security plan for that exact post.
Government Decision 301/2012, the methodological norms for Law 333/2003 — the model “Register of service handover reports” is Annex 2b) and is kept at the post.

Example: at a warehouse guarded 07:00–19:00, the incoming guard arrives at 06:45, signs the handover report, checks the two radios and the flashlight against the inventory, reads in the register that a camera on the north side was faulty during the previous shift, and reports to dispatch that the fault is still there.
Example: the standing orders for an access post allow deliveries only between 08:00 and 16:00; the guard starting the night shift reads them at handover, turns away a delivery arriving at 22:00 and logs the event.

The post is handed over verbally, with no signed report — after an incident nobody can tell which shift it started in.
The post's standing orders changed weeks ago, but the printed copy at the post is still the old one.
Faults spotted at handover are mentioned verbally and lost, instead of being logged and escalated.
The handover register exists only on paper, at the post, so the manager learns nothing until the next site visit.

The post's standing orders are attached to the site, so the guard sees the current version at handover, not an old printout.
Taking over and handing off a shift is confirmed in the app, with time and guard, and dispatch sees in real time which posts are covered.
Equipment assigned to the post shows up at handover from equipment management; a missing item or fault is reported on the spot and reaches the manager.
Events and incidents from the previous shift stay in the site's history, so the incoming guard reads what happened before.