What UV-C does
UV-C lamps emitting at 254 nm neutralize microorganisms by destroying their nucleic acids and disrupting their DNA. In TRESA units the effluent circulates in a closed loop through UV-C chambers so that it receives the required dose.
Why the effluent is conditioned first
TRESA systems condition the effluent before UV-C treatment so that the UV-C dose is effective for that type of effluent. They do this in one of two ways:
- Controlled dilution (TRESA CI and TRESA H): level sensors and a solenoid valve add water to reach the required dilution ratio, 1:2 for CI and 1:10 for the more concentrated hematology effluent treated by H.
- Filtration (TRESA CRD and TRESA CIH): active-carbon filtration, combined with resin ion exchangers in TRESA CRD, reduces chemical contaminants before UV-C treatment.
A typical UV-C cycle
- Effluent flows from the analyzer into the unit’s holding tank.
- It is diluted or filtered, depending on the model.
- The UV-C lamps switch on and preheat.
- A pump circulates the effluent through the UV-C chambers.
- The treated effluent is discharged to an approved drain or sewer connection, subject to local requirements.
Lamps and maintenance
TRESA CI and H use 2 × 95 W UV-C lamps, TRESA CIH uses 3 × 95 W, and TRESA CRD uses a 36 W UV-C lamp. All are rated for a 9,000-hour lamp lifetime.