UV Curing worked example

UV Lamp Life Remaining with rated lamp life remaining of 900 hr: a worked example

Suppose rated lamp life remaining falls to 900 hr. This page works the full calculation at that level so you can see exactly which result moves and by how much. Project days until the next UV lamp swap from rated hours, hours already on the lamp, and current runtime per day.

The inputs for this scenario

  • Rated lamp life remaining: 900 hr (the input this scenario stresses; the baseline uses 1,800)
  • Average daily lamp runtime: 10 hr / day (held at the documented default)
  • Replacement safety factor: 1.2 x (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Days remaining (raw) = useful life remaining รท average daily runtime.
  • Days until planned swap works out to 75 days until replacement at these inputs, and this is the headline figure for the scenario.
  • Days until rated end-of-life works out to 90 days at these inputs.
  • Useful life remaining works out to 900 hr at these inputs.
  • Average daily runtime works out to 10 hr / day at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where rated lamp life remaining sits at 1,800 hr and the headline result is 150 days until replacement, this scenario comes in 50% below the baseline at 75 days until replacement.
  • It divides rated hours remaining by average daily runtime to get raw days, then divides by a safety factor to set a planned replacement day ahead of rated end of life. When the numbers land here, the stressed input is the lever to work; the walkthrough above shows exactly how much each output recovers as it climbs back toward the baseline.

Results at a glance

  • Days until planned swap: 75 days until replacement (headline result)
  • Days until rated end-of-life: 90 days
  • Useful life remaining: 900 hr
  • Average daily runtime: 10 hr / day

Run it with your numbers

  • To rerun this with your own numbers, open the live UV Lamp Life Remaining calculator, set rated lamp life remaining to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.