Finishing worked example

UV Dose and Cure Margin with measured irradiance at part of 430 mW / cm²: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop measured irradiance at part to 430 mW / cm², then walk the calculation through step by step. Calculate UV dose from measured irradiance and exposure time, then compare it with the material cure-dose target and conveyor speed limit.

The inputs for this scenario

  • Measured irradiance at part: 430 mW / cm² (the input this scenario stresses; the baseline uses 850)
  • Exposure time under UV: 1.8 sec (held at the documented default)
  • Material cure-dose target: 1,200 mJ / cm² (held at the documented default)
  • Effective lamp cure-zone length: 2 ft (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: UV dose (mJ/cm²) = measured irradiance (mW/cm²) × exposure time (sec).
  • UV dose works out to 774 mJ / cm² at these inputs, and this is the headline figure for the scenario.
  • Dose margin works out to 64.5 % of target at these inputs.
  • Required exposure works out to 2.79 sec at these inputs.
  • Max speed for target works out to 43 ft / min at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where measured irradiance at part sits at 850 mW / cm² and the headline result is 1,530 mJ / cm², this scenario comes in 49.41% below the baseline at 774 mJ / cm².
  • The practical read: the gap between this scenario and the baseline is entirely attributable to measured irradiance at part, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. Dose assumes irradiance stays constant across the exposure and ignores spectral match — a UVA-heavy datasheet dose is not interchangeable with a UVC lamp reading, so always use a radiometer band that matches the datasheet.

Results at a glance

  • UV dose: 774 mJ / cm² (headline result)
  • Dose margin: 64.5 % of target
  • Required exposure: 2.79 sec
  • Max speed for target: 43 ft / min

Run it with your numbers

  • To rerun this with your own numbers, open the live UV Dose and Cure Margin calculator, set measured irradiance at part to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.