Reaction-to-fire classification in Europe rests partly on a number many laboratories overlook: the gross heat of combustion (PCS) of a product, measured in a bomb calorimeter to ISO 1716. Class A1 and A2 decisions in EN 13501-1 use PCS limits, so the bomb calorimeter is not only a fuel-testing instrument but a classification instrument for building products. The Motis bomb calorimeter is configured for this building-product application.
How the Bomb Calorimeter works
A prepared specimen is burned inside a sealed steel bomb charged with high-pressure oxygen. The heat released raises the temperature of the surrounding calorimeter water by a measured amount; calibrated against a standard reference material, that temperature rise converts into the gross heat of combustion of the specimen in megajoules per kilogram.
Key specifications
| Standard | ISO 1716 - reaction to fire tests for products; determination of the gross heat of combustion (calorific value) |
|---|---|
| Principle | Oxygen bomb combustion with calorimetric temperature-rise measurement |
| Reported value | Gross heat of combustion (PCS), MJ/kg |
What the test reports
- Gross heat of combustion (PCS) of the product
- PCS values for substantial and non-substantial components, as the classification route requires
Applications
Producers of insulation, boards, facings and composite building products use bomb calorimetry for EN 13501-1 classification evidence and for quality control of raw materials. Fuel and research laboratories use the same instrument for calorific value work outside the construction field.
Frequently asked questions
Which standard should I order against?
Order against the standard your reports must cite. The instrument platform is shared across the listed standards, but fixtures, software templates and calibration routines differ, so name the standard (and its year) in your inquiry and the configuration will be matched to it.
How does this relate to the cone calorimeter?
They measure different things. The cone calorimeter measures the rate at which heat is released in a fire scenario; the bomb calorimeter measures the total chemical energy stored in the material. EN 13501-1 classification uses both kinds of data, from different instruments.
What specimen preparation is needed?
ISO 1716 sets out specimen preparation for homogeneous products and for the components of non-homogeneous products. The preparation equipment needed depends on your product forms; describe them in your inquiry.
Configuration, installation and support
Every Bomb Calorimeter is supplied as a configured system, not a bare instrument: the test chamber or frame, the burner or heater assemblies named in the method, the measurement chain and the control software with the report templates for ISO 1716. Before quotation we confirm the installation conditions with you - floor loading and ceiling height for large rigs, exhaust and extraction routes, gas and fuel services, and power supply - because a fire test instrument only produces defensible data when the room around it is right. Commissioning covers assembly, calibration of the measurement chain against the method's own checks, and training of your operators on running the test and maintaining the apparatus. Spare ignition parts, thermocouples and other consumables for the first period of operation can be included in the supply, and the instrument is supported with calibration and maintenance services after installation.
What to include in your inquiry
To quote the Bomb Calorimeter correctly the first time, send: the standard and edition you will test to (ISO 1716); the materials or products you will test and their sizes; the configuration options you already know you need; and the destination laboratory's location and available services. If you are building a new fire laboratory rather than adding one instrument, say so - this apparatus is often planned together with the other instruments in its category, and a combined layout and exhaust plan is cheaper than three separate ones.