Industrial Cybersecurity & OT Risk worked example

Cyber Recovery Spares Buffer with daily recovery spares consumption rate of 5 units / day: a worked example

Push daily recovery spares consumption rate up to 5 units / day and the picture changes. This example computes every intermediate figure at that operating point. Use it when sizing spare HMIs, industrial PCs, network gear, storage media, and recovery kits for OT resilience.

The inputs for this scenario

  • Daily recovery spares consumption rate: 5 units / day (raised for this scenario; the documented default is 2)
  • Recovery spares replenishment lead time: 21 days (unchanged)
  • Recovery spares safety stock held: 12 units (unchanged)

Working through the calculation

  • Applying the documented formula (Cyber recovery spares cycle stock = daily recovery spares demand × recovery spares replenishment lead time) to the inputs above produces each figure below.
  • At this operating point the engine returns 0.02 days for protected days of supply, the number this scenario is built around.
  • At this operating point the engine returns 0.24 days for unprotected days.
  • At this operating point the engine returns 5 pieces for inventory.
  • At this operating point the engine returns 21 pieces / day for daily usage.

How this compares with the baseline

  • Against the tool's baseline example, where daily recovery spares consumption rate sits at 2 units / day and the headline result is 0.01 days, this scenario comes in 150% above the baseline at 0.02 days.
  • It computes the required recovery-spares inventory as cycle stock (daily demand times lead time) plus a safety-stock buffer. 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

  • Protected days of supply: 0.02 days (headline result)
  • Unprotected days: 0.24 days
  • Inventory: 5 pieces
  • Daily usage: 21 pieces / day

Run it with your numbers

  • Every input above is editable in the live Cyber Recovery Spares Buffer calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.