Standards

Q: What does ASTM D240 measure?

D240 reports heat of combustion of a liquid hydrocarbon fuel burned in a bomb calorimeter.

ASTM D240 Heat of Combustion

ASTM D240 is the bomb-calorimeter method for the heat of combustion of liquid hydrocarbon fuels. A weighed sample is burned in oxygen inside a sealed bomb, and the temperature rise of the calorimeter is converted to an energy content. Fuel producers and acceptance labs use the number to check specification heat value — not to describe combustion in an engine or a burner.

The method is written for liquid hydrocarbon fuels. It is not a general calorimetry standard for solids, gases, or formulated lubricants. Gross heat of combustion (the usual D240 report) is also not the same as net heating value; the two differ by the latent heat of the water formed during combustion.

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ASTM Standard at a Glance

Property	Value
ASTM Standard	ASTM D240
Type	Test method
Measures	Heat of combustion (bomb calorimeter)
Applicable samples	Liquid hydrocarbon fuels
Related standards	Other bomb-calorimeter methods for different sample types
Recommended equipment	VeroCal — Oxygen Bomb Calorimeter

Choosing the right equipment for ASTM D240

Bomb calorimetry lives or dies on weigh-up, bomb sealing, jacket temperature, and the corrections the method requires. A dedicated oxygen bomb calorimeter keeps that workflow repeatable.

The Vero Scientific oxygen bomb calorimeter (VeroCal) is the instrument linked to this method.

Frequently Asked Questions

What does ASTM D240 measure?

D240 reports the heat of combustion (gross calorific value) of a liquid hydrocarbon fuel burned in a bomb calorimeter under specified conditions. The result is an energy content, typically in MJ/kg or a related unit from the method.

How does a bomb calorimeter test work?

A weighed sample is burned in a high-pressure oxygen bomb. The temperature rise of the surrounding water jacket, plus corrections defined in the method, gives the heat released.

Which samples fall under ASTM D240?

D240 is written for liquid hydrocarbon fuels. It is not a general “any liquid” calorimetry method, and it is not a substitute for gas calorimetry or for solid-fuel bomb methods.

Does Vero Scientific provide equipment for ASTM D240?

Yes. The oxygen bomb calorimeter (VeroCal) is the Vero Scientific instrument for this D240 workflow.

Is heat of combustion the same as net heating value?

Gross heat of combustion includes the heat recovered when combustion water condenses. Net (lower) heating value subtracts that latent heat. Spec sheets sometimes quote one and mean the other — read the unit and the basis before you compare two numbers.