Following a prefilter process that removes oil and other particulates, deliquescent air dryers apply sodium chloride based desiccant tablets to draw vapor from air in process. The tablets then slowly dissolve into a brine solution, which falls to the bottom of the dryer to be drained at regular intervals. After the treated air exits the top of the dryer it passes through another particulate filter before passing downstream for operation. The volume of brine solution can be monitored via a sight window, and should be drained once per 8-hour shift. Deliquescent air dryers can be used for indoor or outdoor applications, and can take advantage of atmospheric cooling when placed outdoors. As a rule, deliquescent dryers are best placed where the coolest temperatures are available and line pressure is at its highest.