Tunnel Boring & Heavy Civil Equipment worked example

Downtime Cost at 92% attributable downtime share: a worked example in tunnel boring & heavy civil equipment

This scenario runs the downtime cost calculation on the strong side: 92% attributable downtime share, with every other input held at its documented default. Use it when quantifying a delay claim or evaluating a maintenance window to translate stopped hours into the standby and restart dollars at risk.

The inputs for this scenario

  • Lost Tunneling Hours: 36 hours (unchanged)
  • Standby Burn Rate: 2,800 $/hr (unchanged)
  • Attributable Downtime Share: 92 % (raised for this scenario; the documented default is 80)
  • Restart & Mobilization Cost: 18,000 $ (unchanged)

Working through the calculation

  • Applying the documented formula (Total = lost hours x standby burn rate x (attributable share รท 100) + restart cost) to the inputs above produces each figure below.
  • At this operating point the engine returns 110,736 $ for total downtime cost, the number this scenario is built around.
  • At this operating point the engine returns 3,076 $ / piece for downtime cost per unit.
  • At this operating point the engine returns 92,736 $ for variable downtime cost.
  • At this operating point the engine returns 18,000 $ for fixed downtime cost adder.

How this compares with the baseline

  • Against the tool's baseline example, where attributable downtime share sits at 80% and the headline result is 98,640 $, this scenario comes in 12.26% above the baseline at 110,736 $.
  • Use it immediately after a stoppage to quantify the delay for daily cost reports, delay claims, or root-cause reviews, and beforehand to justify redundancy investments. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Total downtime cost: 110,736 $ (headline result)
  • Downtime cost per unit: 3,076 $ / piece
  • Variable downtime cost: 92,736 $
  • Fixed downtime cost adder: 18,000 $

Run it with your numbers

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

Last reviewed 2026-05-12.