High-dust shops don’t just make a mess—they bleed output out of UV systems. Dust coating the reflector scatters and soaks up energy, so the lamp fires but the target gets less. In a closed-reflector UV lamp used for pond sterilization, that drop shows up as weaker microbial kill and process control that drifts. What matters under the hood The Tetra UV pond sterilizer bulb is a high-pressure mercury vapor discharge, built to hold a stable germicidal spectrum centered on 254nm, with solid output in the 365nm band when you need photoinitiation. We keep peak irradiance and spectral distribution within tight tolerances, so the lamp behaves predictably—through warm-up and even when line voltage swings. The full-enclosure reflector uses a high-reflectivity dichroic coating to keep the beam directional, and the sealed geometry prevents dust from settling straight onto the lamp body. Life is long and output stays steady—we routinely track units running 5,000+ hours with under 5% drop. Why it holds up in dirty environments With the enclosure blocking particulate loading, the reflector stays cleaner. The payoff is consistent energy density at the water interface—stable UV dose, fewer process excursions, and less downtime spent wiping parts. You don’t have to overrun the lamp to make up for losses, which translates into fewer replacements and lower operating cost per cycle. A few shop-floor reminders This design is ozone-free, but the reflector and lamp run hot. Check your fixture’s airflow and thermal clearances—tight cabinets can cook components and shorten life. Match the lamp to the ballast and connector type, and make sure the reflector geometry is aligned to the target zone. Output is directional, and if you’re off, you’ll see the dose loss immediately.