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Side cutaway of a vertical septic UV disinfection unit A control box above ground powers a vertical lamp inside a sealed quartz sleeve. Effluent enters from the left and moves around the outside of the sleeve before leaving on the right. Ground level Control box / ballast Riser and lamp cable Lamp inside quartz sleeve Disinfection chamber Inlet from treatment unit Treated effluent outlet Blue arrows show effluent passing around the sealed sleeve.
Illustrative side cutaway of a vertical, inline septic UV unit. Internal flow guides and port locations vary by model. The blue-violet glow represents the lamp in the diagram. Germicidal UV-C itself is invisible.