Since the 16A (and other current ratings) "commando" plugs do not have an internal fuse, any 16A socket should be protected with a 16A current limit. This is because the wiring from the 16A plug to the machine will be designed to handle up to 16A, but if you simply attached a "commando" socket to a 25A supply, potentially 25A could be drawn through that one connector and the associated cables, creating an overheating risk.
It's probably best to install a separate 16A breaker in your board for each 16A socket (i.e., wire them as 'radials'). If this is impossible it might be appropriate to connect a 16A MCB to an existing ring main, and connect the socket to the outlet of that. Small breaker enclosures are available that may be suitable for this application.
The MCB will only protect against over current; an RCD only protects against earth leakage, and an RCBO protects against both but is more costly. Earth leakage - a current difference between live and neutral - is often a sign that something's gone wrong, except in the case of inverter drives where it is sometimes to be expected (or so I'm told).
Of course works like these must only be undertaken by competent electricians.
Cheers
Neil