Cleanroom & Contamination Control worked example

Cleanroom Temperature Excursion Cost at 40% lots expected to require quality disposition: a worked example

Push lots expected to require quality disposition up to 40% and the picture changes. This example computes every intermediate figure at that operating point. a team needs to evaluate temperature controls, alarms, response time, and product hold rules for a temperature excursion scenario

The inputs for this scenario

  • Lots or batches exposed to temperature excursion: 14 lots (unchanged)
  • Cost per exposed lot or batch: 18,500 $ / lot (unchanged)
  • Lots expected to require quality disposition: 40 % (raised for this scenario; the documented default is 35)
  • Fixed HVAC response, deviation, retest, and recovery cost: 22,000 $ (unchanged)

Working through the calculation

  • Applying the documented formula (Variable excursion exposure cost = lots or batches exposed to temperature excursion × cost per exposed lot or batch × lots expected to require quality disposition) to the inputs above produces each figure below.
  • At this operating point the engine returns 125,600 expected temperature excursion cost for expected temperature excursion cost, the number this scenario is built around.
  • At this operating point the engine returns 8,971 $ / piece for temperature excursion cost per exposed lot.
  • At this operating point the engine returns 103,600 $ for variable excursion exposure cost.
  • At this operating point the engine returns 22,000 $ for fixed hvac response, deviation, retest, and recovery cost.

How this compares with the baseline

  • Against the tool's baseline example, where lots expected to require quality disposition sits at 35% and the headline result is 112,650 expected temperature excursion cost, this scenario comes in 11.5% above the baseline at 125,600 expected temperature excursion cost.
  • It computes expected excursion cost as exposed lots x cost per lot x the share expected to need quality disposition, plus fixed HVAC response, deviation, retest, and recovery cost. 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

  • Expected temperature excursion cost: 125,600 expected temperature excursion cost (headline result)
  • Temperature excursion cost per exposed lot: 8,971 $ / piece
  • Variable excursion exposure cost: 103,600 $
  • Fixed hvac response, deviation, retest, and recovery cost: 22,000 $

Run it with your numbers

  • Every input above is editable in the live Cleanroom Temperature Excursion Cost calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.