What is ISO 1928 standard about?

ISO 1928 is an international standard on coke and coal that discusses the procedures to evaluate the efficiency of fuels. ISO 1928 specifies a method for the determination of the gross calorific value of a solid mineral fuel at constant volume and the reference temperature of 25 °C in a combustion vessel calorimeter calibrated by combustion of certified benzoic acid.

The result obtained is the gross calorific value of the analysis sample at constant volume with all the water of the combustion products as liquid water. In practice, fuel is burned at constant (atmospheric) pressure and the water is not condensed but is removed as vapour with the flue gases. Under these conditions, the operative heat of combustion is the net calorific value of the fuel at constant pressure. The net calorific value at constant volume can also be used; formulae are given for calculating both values.

General principles and procedures for the calibrations and the fuel tests are specified in the main text, whereas those about the use of a particular type of calorimetric instrument are described in Annexes A to C. Annex D contains checklists for performing calibration and fuel tests using specified types of calorimeters. Annex E gives examples illustrating some of the calculations. Annex F guides safe to use, maintenance and testing of the calorimeter combustion vessel.

Who is ISO 1928 standard for?

ISO 1928 on coal and coke is beneficial for

Manufacturer of coal and coke
Coal and coke testing laboratories
Supplier and customers of coal and coke

Why should you use ISO 1928 standard?

Gross calorific value is the absolute value of the specific energy of combustion for the unit mass of a solid fuel burned in oxygen in a calorimetric combustion vessel under specific conditions.

ISO 1928 provides guidance to evaluate the gross calorific value, net calorific value, apparatus, preparation of the test sample, calorimetric procedure, calibration and calculation of gross calorific value and net calorific value

As a user of ISO 1928, you can be ensured of the gross calorific value and net calorific value of coal and coke. ISO 1928 helps you to determine the energy content of coal and coke.

With compliance to ISO 1928, you could judge the fuel efficiency and the heat produced by coal and coke which helps you to determine the price of the thermal coal.

What’s changed since the last update?

BS ISO 1928:2020 supersedes BS ISO 1928:2009, which is withdrawn

The main changes compared to the previous edition are as follows:

Change the document title within the scope of TC 27
Editorially update symbols within formulae
Update references
Expand on some derivations
Remove ambiguity around crucible masses
Specify the analysis sample

BS ISO 1928:2020

Coal and coke. Determination of gross calorific value

Published:

31 Oct 2020

Withdrawn:

19 Aug 2025