Has a weapon that can be seen:
1. Security personnel in uniform.
Yup, totally.
2. Privated security personnel in uniform.
Though probably restricted to civilian-made W&G PPG Pistols (slower recharge and a bit less power - the guns the blips try to take our Bester with) and most likely no rifles at all.
Same for alien security personell, like the Centauri guards accompaning important Centauri like Kiro, the Emperor Turhan or Minister Virini (though their guns would actually be a bit better then earthforce Auricon PPG's).
Also licenses to carry melee weapons would be granted to security personell at request - like Ta'lon's blade or the daggers of the Centauri guards accompaning important Centauri like Kiro or Minister Virini.
Soem alein governments would also have the right for their security guys / bodyguards carrying weapons written into treaties so that they wouldn#t need to apply for a license every time someone needed to go to B5.
Has a concealed weapon:
1. Person with a license to carry a concealed weapon.
Including Psi Cops and other EA-licensed persons, as well as Rangers in later days - since B5 security certainly was aware of what the Den'bok really was by then, but closed both eyes to Markus and his toy... though before the IA makes rangers "official" that'd be more of a legal grey area... however, since B5 itself was a legal grey area at that time, well... after IA time the rangers would probably have a status similar to off-station security personell in regard to weapons - they can keep them, but are encouraged not to use them aside from emergencies and directed by station security (y'know, other guys being heroic cuts into Zack's business, and he can't have that, just as Garibaldi before him...).
Will not have a weapon on them:
1. Everyone else on the station including military both enlisted or
officer in uniform.
...unless the situation warrants it. Noone says anything about Sheridan or Ivanova walking around with PPG's at their hips when things become dangerous, or even when things might become dangerous, so it must be allowed. But I suppose that's a matter of "cause" and "orders", as most other uniforms haven't been seen armed yet.
But there seems to be a proliferation of illegal weaponry on B5. I would rule that it is realtively simple to get a blackmarket PPG.
Or every other weapon, from PPG rifles (Born to the Purple) to poisoned Drazi blades (Acts of Sacrifice IIRC).
Well, point of note: if you don't know what to look for, a denn'bok looks like a coke can when collapsed and appears to most scanners as just about as threatening as a balanced paperweight.
Same for many other things... after all, Kalain also got his "crystal spiked knuckles" through customs scanners without a beep. And I'm sure there will be lots of other alien weapons the scanners just won't recognize... however, the scanner databases are updated too, so players trying to be smart should be wary of GM's being the same... once one non-recognized weapon surfaces on the station the scanners will be updated, one can be sure about it. And I presume earthgov will send updated files too, once every six months or so... so it pays to get information before you gamble with the scanners.
Of course, the smarter smugglers will not gamble upon that all, but attempt to evade the scanners entirely, either by bribing some guys, or be being sneaky (scan-proof secret compartments in big cargo modules often get overlooked, since customs just can't take the time to inspect the bulk shipments. Of course, they do make some surprise inspections, especially when they suspect something... of if you have some good electronics expert to disable a door alarm system and open the hatch you can do some unobserved unloading too -as I presume Deveraux did in "Crysalis"-)
And then there's the diplomats... I have no idea if diplomatic baggage is scanned for weapons and they confiscated.
Londo having a disassembled and concealed gun would indicate it might be so (though that may be a touch of purely centauri paranoia too), G'Kar having a nice Dagger and Urza Jaddo bringing Coutari swords on the station -and Londo later having them hanging on his walls for everyone to see and Vir to grab- would indicate it might not. Though that clearly applies only to those who can claim diplomatic status or connections to someone with such...
Finally, there are some who can smuggle Anything on the station if they'd want to. Noone would dare to snoop around Kosh (or have any success if Kosh didn't want him to), and Mr.Morden's associates can certainly bring anyone he wants to do a favor anything he might desire without anyone knowing about it, including Garibaldi and Ivanova. :wink: But of course these guys would seldom come into consideration for PC smuggling need's in your usual game...