Gaskets, Seals, O-Rings & Elastomer Components worked example

Durometer Tolerance with measured durometer of 35 Shore A: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop measured durometer to 35 Shore A, then walk the calculation through step by step. Check whether a measured elastomer hardness reading is inside the specified durometer tolerance window.

The inputs for this scenario

  • Measured durometer: 35 Shore A (the input this scenario stresses; the baseline uses 70)
  • Lower durometer limit: 65 Shore A (held at the documented default)
  • Upper durometer limit: 75 Shore A (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Durometer status = measured durometer checked against lower and upper durometer limits.
  • Inside window works out to 0 outside at these inputs, and this is the headline figure for the scenario.
  • Nearest margin works out to -30 value at these inputs.
  • Lower durometer limit works out to 65 value at these inputs.
  • Upper durometer limit works out to 75 value at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where measured durometer sits at 70 Shore A and the headline result is 1 inside, this scenario comes in 100% below the baseline at 0 outside.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to measured durometer, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. A single durometer reading is point-in-time; Shore A measurements vary with part thickness, temperature, dwell time and operator, so take multiple readings per the test standard.

Results at a glance

  • Inside window: 0 outside (headline result)
  • Nearest margin: -30 value
  • Lower durometer limit: 65 value
  • Upper durometer limit: 75 value

Run it with your numbers

  • To rerun this with your own numbers, open the live Durometer Tolerance calculator, set measured durometer to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.