UV Curing worked example

UV Irradiance at Part at 98% lamp aging derate: a worked example

Push lamp aging derate up to 98% and the picture changes. This example computes every intermediate figure at that operating point. Use it before a radiometer is available - for example sizing a new UV station - or to sanity-check whether a measured radiometer number is consistent with the lamp on the spec sheet.

The inputs for this scenario

  • Rated peak lamp irradiance: 2,400 mW / cm² (unchanged)
  • Focal / reflector efficiency factor: 0.75 x (unchanged)
  • Lamp aging derate: 98 % (raised for this scenario; the documented default is 85)

Working through the calculation

  • Applying the documented formula (Estimated irradiance at part = rated peak × focal/reflector efficiency × aging derate %) to the inputs above produces each figure below.
  • At this operating point the engine returns 1,764 mW / cm² for estimated irradiance at part, the number this scenario is built around.
  • At this operating point the engine returns 1,800 mW / cm² for rated peak irradiance.
  • At this operating point the engine returns 36 mW / cm² for loss to distance / aging.
  • At this operating point the engine returns 98 % for aging derate.

How this compares with the baseline

  • Against the tool's baseline example, where lamp aging derate sits at 85% and the headline result is 1,530 mW / cm², this scenario comes in 15.29% above the baseline at 1,764 mW / cm².
  • It estimates the UV intensity actually reaching the part by derating rated peak irradiance for reflector efficiency and lamp aging. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Estimated irradiance at part: 1,764 mW / cm² (headline result)
  • Rated peak irradiance: 1,800 mW / cm²
  • Loss to distance / aging: 36 mW / cm²
  • Aging derate: 98 %

Run it with your numbers

  • Every input above is editable in the live UV Irradiance at Part calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.