The term explosives is generally self-explanatory. Usually, explosives that are meant to be used against personnel have a large area of effect, which allows them inflict harm upon several beings at once. Explosive type weapons are listed with two distinct areas of effect: primary, wherein full damage is applied to beings, and secondary, wherein beings take only half damage. Area of effect is measured in meters of radius from the explosive. There are three basic classifications for the use of explosives: tactical, traps, and grenades.
Tactical explosives are used to destroy large things such as buildings or ships, and since they must be carefully placed, they have little bearing on personnel combat. Their only interactions are confined to the approach, the placement (briefly), and the getaway; otherwise they are only background considerations or a sudden stop.
Explosive traps require preparation. The fundamental use of an explosive trap involves making the explosive device hidden, and some method of detonation at the correct time. The method of detonation is very easy to contrive, with several variations including proximity sensors, contact sensors, thermal sensors, or simple remote controls used by an observer. To hide a trap requires some skill. The being making the trap rolls two dice, and adds the total to their awareness and any bonus to hide that they may have. If time permits, they may try repeatedly to hide the trap well, but keeping in mind that double sixes are not considered automatic when hiding traps. Each attempt takes only one melee turn. Whether or not a being will actually wander into the effective range of a trap depends on the situation, and the referee. If a being is in the area of a trap they are not aware of, they roll two dice and add the sum to their awareness. If they are looking carefully, they may also add their bonus to locate. If the being has a total greater than the hide value of the trap, they spot it. If they do not spot it, then they behave is if it were not there - unless it is detonated! If there is a tie, the being in danger of being caught by the trap has a bad feeling or becomes nervous, but that is all.
Grenades are the only ilk of explosive that may be used spontaneously in personnel combat, without any prior clandestine preparations. They must be thrown, like an edged weapon, but they don't need to hit to be effective because of their area of effect. The actual description of grenade use in combat can be extremely complex, and referee's are encouraged to be as descriptive as they wish. Unfortunately, if you don't want much complexity, grenades become unsavoury elements of combat. The bare minimum, other than ignoring grenades entirely, is convert every meter of explosive's range of effect as +1 to hit with a thrown weapon, and apply it to the entire target cluster of beings. To make things more realistic, the distance between the target beings can affect the bonus to hit; for example, throwing at two beings that are four (4) meters away from each other you can throw the grenade at one for full bonus, and count the other as four (4) less than full bonus to hit, OR you can throw the grenade in between them so that you attack both of them with two (2) less than full bonus, OR any modulation in between.
Beings carrying explosives are rarely considered anything other than dangerous, just as if they were carrying around a large sign saying, "Does not play well with others." Explosives are extremely hard to conceal, as even a routine scanner sweep will pick up such a device. Beings without scanners will probably be elbowed by the being next to them and be discretely told, "Hey, that zarking jerk is carrying explosives!" and will likely join in the secret plot to shoot the offending being in the back (well away from any potential detonators).