Relative Life Benefit (Arrhenius)

About this tool
Estimate how changing temperature and humidity affects expected lifetime. Enter a reference environment and a new set of conditions. We compute:
  • LFT — life factor from temperature only
  • LFT+AH — life factor with absolute humidity (AH) correction via exponent m

Applicability: This calculator reflects the stable (pre-autocatalytic) regime of film degradation. Once internal acidity becomes high enough, degradation can enter an autocatalytic phase where moisture and temperature effects accelerate non‑linearly. In that regime, apply additional reduction factors and treat these results as optimistic bounds. A precise onset threshold depends on composition and history; use conservative judgment.

Compare a reference environment to a new set of conditions.


If unsure, choose the lower end to be conservative.

RH must be between 0 and 100%.

Baseline Life at Reference

Baseline life at the reference environment. We multiply by LF to estimate life under new conditions.

Moisture Sensitivity (m)

Humidity correction assumes k ∝ AH^m. Try m = 0.5 and m = 1.0 to bracket effects; higher m means moisture matters more.

Activation Energy (Ea)

Ea controls temperature sensitivity in the Arrhenius term. Higher Ea ⇒ larger life benefit when you cool.
Absolute Humidity (Ref, g/m³)
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Absolute Humidity (Cond, g/m³)
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k(T only) ratio = kcond/kref
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k(T+AH) ratio
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Relative Life Benefit LFT (temp only)

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Relative Life Benefit LFT+AH (includes humidity)
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Estimated life from baseline

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How to use the two results:
  • Temperature-only (LFT): Classic Arrhenius result that ignores moisture. Use this when humidity is unknown, poorly controlled, or when you want a temperature-only baseline.
  • Temperature + AH (LFT+AH): Adjusts for absolute humidity using the moisture sensitivity exponent m. Use this when humidity is measured/controlled or when you want a more realistic bound for moist environments.
Recommendation: Treat LFT and LFT+AH as a bounding pair: LFT is the drier-side bound; LFT+AH shifts with moisture. If you’re unsure about m, try 0.5 and 1.0 to bracket sensitivity.
How to read Life Factor (LF):
LF is a multiplier applied to your baseline life at the reference environment.
  • LF > 1 → a life benefit under the proposed conditions (longer life than reference).
  • LF < 1 → a life reduction under the proposed conditions (shorter life than reference).
Use LFT for temperature-only and LFT+AH to include humidity (via exponent m).
Assumes stable (pre-autocatalytic) regime; apply additional reductions or re-baseline if autocatalysis is suspected.