New conf.json option "safeZonePreventAllDamageToPlayers" (default false) which will prevent all damage to players while they're in a Safe Zone; note that attack damage from other players and monsters is still prevented regardless

src/com/massivecraft/factions/Conf.java

@@ -99,6 +99,7 @@ public class Conf {
 	public static boolean safeZoneDenyBuild = true;
 	public static boolean safeZoneDenyUseage = true;
 	public static boolean safeZoneBlockTNT = true;
+	public static boolean safeZonePreventAllDamageToPlayers = false;
 	
 	public static boolean warZoneDenyBuild = true;
 	public static boolean warZoneDenyUseage = true;

src/com/massivecraft/factions/listeners/FactionsEntityListener.java

@@ -82,10 +82,12 @@ public class FactionsEntityListener extends EntityListener {
 			if ( ! this.canDamagerHurtDamagee(sub)) {
     			event.setCancelled(true);
     		}
+		} else if (Conf.safeZonePreventAllDamageToPlayers && isPlayerInSafeZone(event.getEntity())) {
+			// Players can not take any damage in a Safe Zone
+			event.setCancelled(true);
 		}
 	}
 	
-	
 	@Override
 	public void onEntityExplode(EntityExplodeEvent event)
 	{
@@ -126,6 +128,16 @@ public class FactionsEntityListener extends EntityListener {
 		}
 	}
 
+	public boolean isPlayerInSafeZone(Entity damagee) {
+		if ( ! (damagee instanceof Player)) {
+			return false;
+		}
+		if (Board.getFactionAt(new FLocation(damagee.getLocation())).isSafeZone()) {
+			return true;
+		}
+		return false;
+	}
+
 	public boolean canDamagerHurtDamagee(EntityDamageByEntityEvent sub) {
 		Entity damager = sub.getDamager();
 		Entity damagee = sub.getEntity();