"Fuse box" and "consumer unit" mean the same thing, just from different eras. If yours still looks like something from decades ago, it might be time for an upgrade. Here's how to actually tell.
The clearest sign is what's inside the box itself. If you open the cover and see ceramic fuse holders with actual wire running through them rather than switch style breakers, that's a rewireable fuse board, a design that predates modern safety standards by a long way. It's not automatically dangerous, but it doesn't offer anywhere near the protection a modern consumer unit does.
A closely related sign is missing RCD protection. If your board shows nothing but rows of small rectangular switches labelled with amp ratings, and there's no larger test button anywhere on the unit, there's a real chance you have no RCD protection at all. RCDs cut power in milliseconds if they detect a fault, and their absence is one of the most common reasons an EICR comes back Unsatisfactory.
Beyond what the board looks like, listen and smell too. Any buzzing, humming, or crackling from the unit is never normal, and usually points to a loose connection or arcing. A burning smell or visible scorch marks around the casing means something is already overheating, worth getting checked without delay.
Frequent, unexplained tripping is worth paying attention to as well. Older boards sometimes simply fail to pick up faults that a modern one would catch immediately.
Worth saying plainly: being old, or being made of plastic rather than metal, doesn't automatically mean a fuse board needs replacing. The real test is whether it passes a proper inspection and offers the protection your home actually needs today.
For landlords specifically, this matters on a deadline. If an EICR comes back Unsatisfactory because of the consumer unit, the remedial work typically needs sorting within 28 days of the report.