UV Dose for BWMS (rough empirical estimate)

Order-of-magnitude UV dose for a BWMS reactor as a function of lamp UV-C output, flow, and UV transmittance. Empirical fit only: actual BWMS dose-credit requires biodosimetry.

Ballast WaterUV

This is a rough empirical estimate, not a regulatory dose calculation. Actual UV dose under MEPC.300(72) Annex 5 must be established via biodosimetry on the specific reactor under design flow and at the worst-case UV transmittance condition. Vendor-published curves (lamp output vs flow vs UVT) are the authoritative source for a given BWMS. Use this calc to ballpark whether a reactor configuration is in the plausible range, never as compliance evidence.

Total lamp UV-C outputWTreatment flowm³/hUV transmittance at 254 nm%Target dosemJ/cm²

Effective UV dose (estimate): 1mJ/cm²

Status: Short by 299

Changing the inputs requires JavaScript. The calculator above shows its default inputs and result. The formula, symbols, and regulatory sources are shown in the Formula section below.

Formula, assumptions, and limits

\text{Dose} \approx \frac{P \cdot 3600}{Q \cdot \text{volume}} \cdot T_{UV}^{1.5}

Symbol	Meaning	Unit
$P$	Lamp UV-C output	W
$Q$	Flow	m³/h
$T_{UV}$	UV transmittance at 254 nm

Source: MEPC.300(72) BWMS Code

In short

UV dose (mJ/cm\u00b2) delivered by a BWMS reactor at a given flow and lamp power, with UV transmittance correction.

Learn the theory BWM Convention 2004: Ballast Water Management