Combustible Dust Hazards
Know your risk to prevent dust explosions with the help of our combustible dust services
Organizations that are aware of the hazards of combustible dusts and how to manage or eliminate the dangers they pose can effectively avoid the catastrophic effects of dust explosions: loss of life and property, injury, damages, interrupted production, litigation and adverse publicity. Unfortunately, these incidents occur all too frequently, indicating a lack of sensitivity to the topic and perhaps a lack of access to appropriate expertise.
Our engineers have a strong background in combustible dust issues, strengthened through years of experience. We offer a comprehensive package of services, helping you to identify hazardous materials and to assess associated risks. Testing, which we carry out in our own state-of-the-art laboratories, is a start, but interpreting the data and translating our findings into practical solutions through expert consulting and training is our strength. Whether advising you on the choice and design of explosion protection systems, performing risk assessments or recommending training, we never lose sight of the big picture: a safe and secure working environment within a thriving organization.
The knowledge and resources we bring in as a global organization make us a natural choice for companies looking for a reliable partner to address process safety topics in general, and combustible dust challenges in particular. Our laboratories are ISO 9001 compliant and GPL (Good Practice Laboratory) certified, while our process safety experts combine the highest qualifications with experience and a real passion for the teamwork it takes to design sustainable safety solutions
Consultancy advice and top-of-the-line combustible dust testing
Our portfolio of services related to combustible dusts reflects our comprehensive approach to safety, encompassing consulting, testing and training. We offer expertise in:
- Hazard Identification
- Determining Combustibility and Explosibility Hazards
- Dust Hazard Analysis (DHA)
- Dust Hazard Management
- Training and Competence Development
- NFPA 652 Compliance
One of our consulting teams can help you select the most appropriate tests and the most cost-effective manner to respond to your needs. The tests we offer include:
Dust Explosion Screening
- Group Go/NoGo Classification: determines whether a powder or dust is explosible (Type Go) or non-explosible (Type No Go) when exposed to an ignition source when in the form of a dust cloud.
Ignition Sensitivity
- Minimum Ignition Energy (MIE): determines the minimum energy of an electrostatic or mechanical spark capable of igniting dispersed dust under ambient conditions.
- Minimum Ignition Temperature (Cloud): determines the minimum temperature of a hot surface capable of igniting a dust cloud
- Minimum Ignition Temperature Layer (MIT Layer): determines the minimum temperature of a hot surface capable of igniting a powder layer (5 mm in depth).
Flammable Limits
- Limiting Oxygen Concentration (LOC): determines the highest oxygen concentration at which ignition of dispersed dust at ambient temperature and pressure is not possible.
- Minimum Explosible Concentration (MEC): determines the minimum concentration of a dust at which ignition is possible.
Explosion Severity
- Dust Explosion Severity: measures a powder’s explosion severity according to specific pressure parameters
Frequently Asked Questions
- Q: What types of materials qualify as combustible dusts?
- Q: What causes a dust or powder to ignite or explode?
- Q: How can I get started with confronting these dust hazards?
- Q: What are some of the measures that make up a “Basis of Safety”?
- Q: What sort of testing is required?
- Q: How can DEKRA Process Safety help?
A: More than 70% of powders handled in industry are recognized as flammable. Processing powdered sugar, flour, aluminum powder and even aspirin can create significant risk of fire and explosion, and this can occur when the substance is in the form of a layer of powder, a cloud of dust or during decomposition. Of course, there are other sources of combustible dust and new materials are constantly being developed that require testing, but it is important to realize that even substances that are not normally associated with flammability or explosivity can indeed cause disastrous incidents. These materials are made more dangerous by the lack of awareness surrounding them.
A: In general, fires require fuel, an oxidant and an ignition source, while an explosion requires, in addition, mixing and confinement. In process industries fuel can be present in the form of a dust or powder--flour, for instance--while the oxidant is furnished by the air. Ignition sources in this context include a spark, a flame or elevated temperature. The mixing of the air and the flour to form a dust cloud, combined with confinement and the presence of a spark or hot surface creates the preconditions for an explosion.
A: We recommend a two-pronged approach: prevent the conditions required for fire or explosion to occur and protect your personnel and process from the effects, if an incident does take place. To do this, you need to establish a “Basis of Safety”, or a combination of measures aimed at prevention and protection. First, you have to examine the dust and evaluate its:
- Flammability
- Potential to form a dust cloud
- Sensitivity to ignition sources
- Explosion limits
- Explosion severity
Much of this information may be available on the substance’s Material Safety Data Sheet (MSDS).
A: Prevention measures include avoiding the formation of flammable atmospheres, keeping operations outside of the flammable range or operating in an environment where the oxygen content remains below the lowest concentration necessary to support combustion. Ignition sources can be avoided as well if the ignition sensitivity of the powder is known. When preventative measures are not acceptable as the ultimate “Basis of Safety”, dust explosion venting, suppression and containment may be required.
A: We have adopted a methodical approach to dust testing that starts with an explosive properties evaluation. This includes a functional group examination, small scale screening tests and oxygen balance/CHETAH calculations. At this point, dusts are either labeled not explosive or potentially explosive. The latter group are subjected to an explosivity analysis which includes DSC screening and UN sensitivity testing. Some of these potentially explosive dusts are then regrouped as not explosive.
Those that are significantly explosive cannot be immediately incorporated into your processes. Other options need to be considered such as:
- Subcontracting synthesis and handling to a third-party specialist;
- Handling the substance in diluted form so that its hazardous properties are reduced to an acceptable level;
- Or considering alternative substances.
Materials that are labeled not explosive may still create an appreciable fire or dust explosion risk. For this reason, they undergo further testing: a dust explosion screening, fire analysis and thermal stability screening .
A: We can help whether you are just starting to understand and address combustible dust hazards or would like to introduce new materials into processes that have already been subject to evaluation and analysis. Our experts can consult with you to identify your hazards, carry out a Dust Hazard Analysis (DHA) and design a dust hazard management plan. We can help you choose the right tests and interpret and apply their results. Our training and competence courses teach staff about the dangers of dusts and powders and how to avoid disasters. We are also experienced in assisting with NFPA 652 compliance . We are your quintessential partner for safety around combustible dusts, offering a full range of services under one roof.
