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Chemical Reaction Hazard Testing

Our testing combines reaction calorimetry and differential scanning calorimetry (DSC) techniques to identify thermal instability, decomposition risk, and runaway reaction potential.

Uncontrolled exothermic behaviour can escalate fast, creating safety risk, operational disruption, regulatory exposure, and lasting reputational damage. DEKRA’s chemical reaction hazard testing gives you decision-ready data to define safe operating limits, validate safeguards, and improve confidence in safe scale-up and routine operation.

Navigating the reactive side of chemical processing

Reactive risk is rarely limited to the “planned” chemistry. Side reactions, contamination, overheating, loss of cooling, hold times, and process upsets can introduce conditions where thermally unstable substances and mixtures behave unpredictably, including the potential for runaway exothermic reactions. DEKRA helps you translate laboratory evidence into practical controls that work in real plant conditions.

Linking laboratory observations to plant-scale behaviour typically involves a sequence of tests including DSC analysis, gas analysis methods and targeted calorimetry — such as reaction calorimetry and accelerating rate calorimeter (ARC) studies.

Benefits of Chemical Reaction Hazard Testing

Reduced major incident risk: Identify and characterise reactive chemical hazards before they reach the plant.
Stronger process decisions: Use process safety testing to define safe limits, credible deviations, and control requirements.
Improved scale-up reliability: Reduce surprises during scale-up and tech transfer through evidence-led testing and interpretation.
Practical recommendations: Turn results into actions that support safety, quality, and operational continuity.

Industries benefiting from our expertise

Our approach to give you confidence and mitigate risk

Our work is designed to match your decision point, whether that is early screening, scale-up readiness, or relief and protection validation.

Typical process

1. Pre-assessment and scope

Clarify your chemistry, operating conditions, credible deviations, and what you need the data to decide.

2. Hazard identification and screening

Establish whether decomposition, side reactions, or instability could drive escalation, including tools such as CHETAH where appropriate, screening can involve differential scanning calorimetry (DSC) or other thermal screening approaches to detect early exothermic activity.

3. Targeted calorimetry and stability characterisation

Generate decision-quality results using techniques matched to your system and risk profile this step may include calibrated reaction calorimetry (e.g. Mettler RC1) or accelerating rate calorimeter (ARC) testing to quantify thermal and pressure escalation potential.

4. Pressure and relief considerations

Where relevant, focus on pressure generation mechanisms and what they imply for protection measures.

5. Clear reporting and practical recommendations

You receive outputs that support engineering decisions, change management, and safe operating envelope definition.

Background on selected methodologies

The CHETAH program (The ASTM program for Chemical Thermodynamic and Energy Release Evaluation) is a unique tool for predicting both thermochemical properties and certain “reactive chemical hazards” associated with a pure chemical, a mixture of chemicals or a chemical reaction. CHETAH is useful for classifying materials for their ability to decompose with violence, for estimating heats of reaction or combustion, and for predicting lower flammable limits.

DSC is a method for thermal analysis using small samples of a few milligrams (micro-thermal analysis). Since DSC works on a micro scale using only a few milligrams of substance, it is possible to investigate highly exothermic processes under extreme conditions without any risk. The relatively small sample quantities used in DSC ensure sufficient temperature homogeneity within the sample and thus even high heat outputs can be measured quantitatively. In addition, the duration of an experiment in the scanning mode is only several hours, making the DSC technique a very rapid and powerful method for screening purposes.

Carius tube is a screening tool for thermal stability screening to search for exothermic activity and gas generation. Carius tube screening tests can detect exothermic activity such as the onset temperatures, identify pressure effects such as the onset of permanent gas generation and ultimately discern the quantity of gas generated during the test. The permanent gases generated can be analyzed by various analytical techniques such as GC-MS and GC-FID.

The ARC is an automated laboratory instrument, which aids in experimentally determining the time, temperature, and pressure relationships of any exothermal reaction in a confined adiabatic environment. The data produced by the ARC can be applied to the evaluation of thermal and pressure hazard potentials of reactive chemicals and can be used for specifying plant protection measures including emergency relief system designs using DIERS technology.

The Mettler RC1 reaction calorimeter is a computer controlled laboratory reactor that balances heat and mass flows. It is an excellent tool for studying the thermal characteristics of the desired reactions and for assuring safe process performance. RC1 data provides information such as energy of reaction, specific heat, adiabatic temperature rises and heat transfer coefficients. RC1 can be used for process development and optimization by studying the behavior of chemical processes in relation to changing process parameters, such as temperature, dosing, stirring, concentration and catalyst.

This instrument enables plant-scale runaway reactions to be directly simulated in the laboratory. In addition, the Dewar calorimeter ensures direct simulation of reactors up to 25 m3, yields highly accurate test data and an accurate representation of multi-phase reaction mixtures, can be run batch, semi batch or gaseous batch and is a highly economic solution for combining process safety and development studies. The data from a Dewar experiment can be used for specifying plant protection measures including emergency relief system designs using DIERS technology.

The Vent Sizing Package was originally developed during the DIERS project in the mid-1980s to collect data for vent sizing calculations on runaway exothermic reactions and decomposition; it was later commercialized as the VSP2™. Unlike the Adiabatic Dewar and ARC systems, which use thicker wall test cells to withstand high pressures, the 120 cm3 VSP2™ test cells are thin walled with a lower phi factor. This unit is one of the most well-known adiabatic calorimeters in the world and is particularly popular in the USA for the study of runaway reactions.

Why choose DEKRA?

Global Expertise

Specialist expertise and laboratory capability to make reactive testing worthwhile, not theoretical.

Process Safety

Strong process safety focus, including reaction studies and tests under elevated pressure and reflux conditions.

Trusted Guidance

A clear commitment to protecting people, operations, and reputation, with recommendations grounded in real use.

Tailored Solutions

Solutions adapted to your needs, with practical and economic recommendations to improve your process.

Meet the experts

At DEKRA UK, our team of experts is at the heart of our commitment to process safety. Comprised of highly skilled scientists with extensive experience in process safety testing, our team works diligently in state-of-the-art labs to ensure the highest standards of safety and reliability. Our experts help you interpret DSC testing results and design robust calorimetric strategies that de-risk scale-up decisions and improve safety outcomes.

Frequently Asked Questions

A: It is used to identify and characterise reactive chemical hazards, including the potential for runaway exothermic reactions, thermal instability, and escalation risks during scale-up and operation.

A: Ideally before scale-up, tech transfer, or any process change that affects heat removal, concentrations, contaminants, residence time, or operating conditions.

A: Yes. Testing can be selected to understand pressure generation and support relief considerations, including VSP2™ and DIERS-aligned approaches where relevant.

A: Depending on your needs, this may include DSC, reaction calorimetry, ARC, adiabatic Dewar calorimetry, CHETAH, and gas analysis approaches such as Carius tube testing.

A: Differential scanning calorimetry testing (DSC) is a rapid thermal analysis method for screening exothermic behaviour and decomposition onset. When early screening suggests risk, it can be followed by reaction calorimetry or accelerating rate calorimeter (ARC) testing to quantify heat release and define safe operating limits.

A: Clear results and practical recommendations to support safe limits, safeguards, and decisions for process safety testing and safe scale-up.

A: DEKRA Process Safety helps organisations reduce risk and improve decision-making in high-hazard operations by combining specialist expertise with evidence-led testing and practical recommendations. Support typically includes:

Identifying and characterising process hazards and credible escalation scenarios
Generating decision-ready data through targeted laboratory testing
Translating results into clear operating limits, safeguards, and actionable controls
Supporting safe scale-up, process change, and incident prevention through structured, proportionate guidance
Delivering reports and recommendations that are practical to implement and aligned to operational realities

We also supply instruments for self-sufficient safety data and maintenance.

We can provide you with equipment for standard tests, as well as customised apparatus for your specific needs. Download our brochure or get in touch today.

DEKRA Safety Instruments

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