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Calcimator

Flash Point Estimator

Estimate blend flash point from component fractions for NFPA/GHS safety classification.

Inputs

%
°F
%
°F
%
°F

Results

Blend Flash Point

146 °F

Blend Flash Point63 °C
NFPA Classification4
GHS Flammable Liquid Category3
Storage Restriction Level1
Light Fraction20%
Medium Fraction50%
Heavy Fraction30%
How to Use This Calculator
  1. Enter Light Fraction Volume, Light Fraction Flash Point, and Medium Fraction Volume.
  2. Set Medium Fraction Flash Point, Heavy Fraction Volume, and Heavy Fraction Flash Point.
  3. Review the Blend Flash Point (°F) result.
  4. Use Blend Flash Point (°C) and NFPA Classification to inform your decision.
  5. Use the chart to visualize the results and explore different scenarios by adjusting inputs.

How the result changes with Medium Fraction Flash Point

Medium Fraction Flash PointBlend Flash Point
85112 °F
173157 °F
278203 °F
365236 °F

What each input means

Light Fraction Volume
Volume percentage of light components (naphtha, gasoline range).
Light Fraction Flash Point
Flash point of the light fraction in °F. Gasoline is typically -45°F.
Medium Fraction Volume
Volume percentage of medium components (kerosene, diesel range).
Medium Fraction Flash Point
Flash point of the medium fraction in °F. Diesel is typically 125–180°F.
Heavy Fraction Volume
Volume percentage of heavy components (residual fuel, lube base).
Heavy Fraction Flash Point
Flash point of the heavy fraction in °F. Residual fuel oil is typically 300–400°F.

What each result means

NFPA Classification
1=Class I, 2=Class IC, 3=Class II, 4=Class IIIA, 5=Class IIIB
GHS Flammable Liquid Category
1=Most Hazardous, 4=Least Hazardous
Storage Restriction Level
3=Most Restrictive, 1=Least Restrictive

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Light Fraction Volume = 20, Light Fraction Flash Point = -45, Medium Fraction Volume = 50, Medium Fraction Flash Point = 150 = 6 input(s) provided
  2. Calculate Blend Flash Point
    Blend Flash Point
    146 = 146
  3. Calculate Blend Flash Point
    Blend Flash Point
    63 = 63
  4. Calculate NFPA Classification
    NFPA Classification
    4 = 4

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