Yellow Misama, Deep Purple Smog, and Black Smoke. Upon detecting traces of an imminent threat, a patrolling member of the Fogwatch will fire a colored flare into the sky at their location, indicating the nature of the gas present. Regularly-placed watchtowers scan the skies for these signals, and on sighting will start working the sirens, warning the populace to get indoors or evacuate. This defense system has saved countless lives as people respond like a well-oiled machine. One of the things that makes scavenging in the Grey District so dangerous is the lack of these warnings.
Since the patrolling Fogwatch members are often at the cusp of the incoming gases, they are provided with gasmasks as proof against the initial lung- and eye-burning effects of Yellow Miasma and some Black Smokes, as well as grappling hooks in case of being caught away from accessible entrances to shelter.
Members of the Fogwatch patrol singly during the day, but on the dangerous night streets travel in pairs, with the supplementary Fogwatcher carrying crossbow and saber to ward off the lesser terrors of the night. It is not uncommon to hear of the flares being shot offensively as desperate measures.
Fogwatchers are forbidden from smoking on duty as scent is the earliest means of identifying many gaseous threats. As such, khat chewing is particularly popular among the ranks.