Environmental Test Chambers & Reliability Labs worked example

Test Interruption Cost at 72% affected project share: a worked example

This worked example runs the test interruption cost numbers for a tougher week than the baseline: 72% affected project share instead of the typical 100%. Estimate cost impact of an interrupted reliability test from lost chamber-hours, loaded hourly cost, affected share, and restart costs.

The inputs for this scenario

  • Lost or invalid chamber-hours: 64 chamber-hr (held at the documented default)
  • Loaded cost per chamber-hour: 92 $ / chamber-hr (held at the documented default)
  • Affected project share: 72 % (the input this scenario stresses; the baseline uses 100)
  • Restart, inspection, and investigation cost: 1,850 $ (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Lost chamber-time cost = lost chamber-hours × loaded cost per chamber-hour × affected project share.
  • Total test interruption cost works out to 6,089 $ at these inputs, and this is the headline figure for the scenario.
  • Interruption cost per lost chamber-hour works out to 95.15 $ / chamber-hr at these inputs.
  • Lost chamber-time cost works out to 4,239 $ at these inputs.
  • Restart, inspection, and investigation cost works out to 1,850 $ at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where affected project share sits at 100% and the headline result is 7,738 $, this scenario comes in 21.31% below the baseline at 6,089 $.
  • Use it after an abort to quantify the event, or in advance to estimate the exposure a given interruption mode carries when building a business case for redundancy. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Total test interruption cost: 6,089 $ (headline result)
  • Interruption cost per lost chamber-hour: 95.15 $ / chamber-hr
  • Lost chamber-time cost: 4,239 $
  • Restart, inspection, and investigation cost: 1,850 $

Run it with your numbers

  • To rerun this with your own numbers, open the live Test Interruption Cost calculator, set affected project share to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.