Atlantium OPG004200 — Quartz sleeve for the 295 mm, 4.2 kW lamps of the RZ300 series; overall length 368 mm. The quartz element isolates the medium-pressure lamp from the water while passing the germicidal UV output into the treatment chamber. Quartz fouls and solarises in service; it is cleaned or replaced when the dedicated UV intensity sensor reading cannot be recovered by lamp replacement or wiping. Replace the sealing O-rings whenever the sleeve is removed. Spare part for Atlantium Technologies Hydro-Optic (HOD) UV water disinfection systems, which use medium-pressure lamps, a quartz treatment chamber working by total internal reflection, one UV intensity sensor per lamp and continuous UV-transmittance monitoring; installed in aquaculture, dairy and beverage process water, municipal drinking water, power-plant and industrial water treatment.