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UV Disinfection Calculator
Dose selection (UVDGM) · UVT correction · electrical power & lamp-count estimate · validation rules
iWhat this tool does
UV dose is a physical quantity — irradiance × time — validated by bioassay. This tool turns your permit into a
design dose, corrects for water quality (UVT), and estimates the power and lamp count for budgeting. Final lamp counts come from a
vendor's validated dose-delivery curves — this sheet makes every vendor bid against the same basis.
1Flow & discharge target
Dose presets below follow the UVDGM / NWRI validated RED basis:
30 mJ/cm² = municipal coliform floor (TCEQ §217.295) · 40 = 4-log bacteria · 80 = reuse-class (Title-22 grade).
Click a preset or type your own.
UVT → lamp-factor table (reference)
| UVT₂₅₄ | Relative lamps (65 % = 1.00) |
|---|---|
| 75 % | 0.75 |
| 70 % | 0.87 |
| 65 % | 1.00 |
| 60 % | 1.15 |
| 55 % | 1.35 |
Literature: every 5 points below 60 % adds ~15–20 % lamps. Interpolated linearly here.
Results — dose & reactor estimate
Peak flow to UV
—m³/h
Electrical power
—kW
Lamp count (est.)
—lamps
| Item | Value | Unit |
|---|
Dose table — reference (UVDGM RED)
| Organism | 2-log | 3-log | 4-log | mJ/cm² |
|---|---|---|---|---|
| E. coli / bacteria | 15 | 25 | 40 | |
| Giardia lamblia | 5.0 | 11 | 20 | |
| Cryptosporidium | 5.8 | 12 | 22 | |
| Hepatitis A | 21 | 30 | 45 | |
| Adenovirus | 85 | 140 | 186 |
RED = reduction-equivalent dose from validated biodosimetry [1]. Note adenovirus: if virus credit matters (reuse), the dose is set by adenovirus, not bacteria.
UV instrumentationMAPPED TO OUR RANGE
| Duty | Instrument | Model / spec | Qty |
|---|
Quote the UV train's instruments at factory price
Flow-paced dose control needs reliable flow and effluent-quality signals — we supply those at the manufacturer's ex-works price with no mark-up (our margin is the export tax rebate).
Request a quote for this duty ← Clarifier upstream Design Manual home
Response within 24 hours · Your inputs stay in your browser — nothing is uploaded.
Sources & parameter basis
| [1] | US EPA, UV Disinfection Guidance Manual (UVDGM) / NWRI guidelines — RED tables by organism & log credit. |
| [2] | TCEQ §217.295 — 30 mJ/cm² floor for activated-sludge effluent; UVT ≥ 65 %; TSS/BOD ≤ 30 mg/L; bioassay validation (scale ≤10×, ≥4 lamps). |
| [3] | UV retrofit engineering guidance (2026) — UVT bands 60–75 % secondary, peak factor 2.0–2.5, single-module-out redundancy 75 %, dose escalation for reuse 40–80. |
| [4] | UV supplier engineering data — LP 254 nm / MP polychromatic characteristics, lamp life, sleeve fouling, intensity sensors, energy band 0.02–0.05 kWh/m³ @30 mJ/cm². |
This is a budgeting estimate, not a procurement design. Regulatory UV design requires a
bioassay-validated reactor matched to your UVT and peak flow. Use the numbers above to set the design basis and compare vendors —
then procure against their validated dose-delivery curves.
Questions about a duty, a specification, or transparent sourcing? Contact our application engineers →