In today’s episode of the Dust Safety Science podcast, Dr. Andrezj Wolff from Grupa Wolff based out of Krakow, Poland, discusses a web-based risk assessment solution called AW-OZ. With his team, he has conducted more than 350 explosion risk assessments for various industries. He has also delivered numerous high tech safety audits and provided ethics training to over 100 industrial companies. Over these 30 years, he has gained extensive working experience in process and explosion protection for different types of process equipment and process lines across also different industries.
What Is AW-OZ and Why Was It Developed?
AW-OZ is a web-based tool designed for conducting quantitative hazard risk assessments of bulk material processing equipment that handles combustible and explosive dust. Developed by Dr. Andrezj Wolff and his team at Group Wolff, it provides a more objective and data-driven approach to explosion risk assessments.
For industries that process hazardous materials, having a reliable and accurate tool is essential. Traditional risk assessments often rely on subjective evaluations, such as estimating the frequency or likelihood of certain events. These methods can be prone to human error, leading to incorrect conclusions that might impact safety.
Dr. Wolff emphasized that AW-OZ was born out of the need to improve how explosion risks are assessed. His motivation to develop this tool came from his extensive experience in the field. Over the years, he saw the limitations of descriptive and subjective approaches in assessing explosion hazards. By focusing on process data such as material properties, equipment specifications, and operational parameters, AW-OZ ensures a more precise evaluation of explosion hazards. The tool addresses a critical gap in the industry—removing guesswork and offering a rigorous approach to safety.
What is Article 4 of the ATEX User Directive?
AW-OZ was created with compliance in mind, specifically with respect to the ATEX User Directive, which is widely used in Europe. Article 4 of this directive outlines the essential elements that must be included in an explosion risk assessment. These include:
- The likelihood of explosive atmospheres occurring and persisting.
- The presence and effectiveness of ignition sources, including electrostatic discharges.
- The design and installation of equipment and processes, and their interactions.
- The anticipated scale and impact of a potential explosion.
Dr. Wolff explained that AW-OZ is fully aligned with these requirements. The tool uses real process data to assess potential hazards and make recommendations for explosion protection systems. This quantitative assessment makes AW-OZ particularly valuable for industries looking to meet ATEX standards in a more precise and reliable way.
Traditionally, explosion risk assessments under the ATEX User Directive have been somewhat subjective. For example, human evaluators would estimate the likelihood of certain events or the effectiveness of ignition source controls. However, this can lead to inconsistencies or inaccuracies. AW-OZ removes this element of subjectivity by basing its assessments on measurable, objective data, which leads to more consistent and accurate results.
What is Article 4 of the ATEX User Directive?
AW-OZ was developed as a result of Dr. Wolff’s extensive experience in conducting explosion risk assessments. Over the course of his career, he and his team at Group Wolff have conducted more than 350 such assessments across various industries. From this experience, it became clear that risk assessments needed to be more data-driven and less reliant on subjective interpretation.
The tool integrates process data—such as dust characteristics, equipment dimensions, and operating conditions—to calculate the potential hazard. Dr. Wolff explained that early explosion risk assessments often struggled with the challenge of properly incorporating quantitative data. AW-OZ solves this issue by building assessments based on detailed process information, such as:
- The minimum ignition energy (MIE) of the dust.
- The lower explosion limit (LEL).
- The physical characteristics of the equipment being used (e.g., volume, height, slenderness).
- The operational conditions, such as whether the equipment runs continuously or in batches, the presence of dust collection systems, or whether a magnetic separator is used in the process.
This approach ensures that the risk assessment is based on solid data, minimizing the risk of human error. After calculating the hazard value, the tool assigns the risk to one of four levels and suggests appropriate protection systems based on the findings. AW-OZ is a comprehensive solution designed to support the evaluation of both existing and new equipment.
What Types of Equipment Can AW-OZ Assess?
At present, AW-OZ can evaluate various types of equipment used in bulk material processing. These include:
- Storage silos and intermediate silos.
- Filters and cyclones.
- Bucket elevators, screw conveyors, and scraper conveyors.
- Pipes, channels, and chutes.
In addition to these types of equipment, Dr. Wolff’s team is working to expand the tool’s capabilities to cover more complex processes, such as milling, grinding, mixing, drying, heating, and cooling. Each of these processes presents its own unique set of challenges when it comes to explosion risk assessments. For example, milling and grinding equipment often generate fine dust particles that can become explosive under the right conditions. The challenge lies in accurately assessing the risk for each type of equipment, as their designs can vary significantly from one application to another.
The goal is to make AW-OZ applicable to a broad range of industrial processes. By expanding the tool’s database to cover additional equipment, the team hopes to make it even more useful for industries that handle combustible dust.
Who Is the Intended User of AW-OZ?
AW-OZ is designed for professionals who are responsible for conducting or overseeing explosion risk assessments. Dr. Wolff outlined several key user groups that could benefit from the tool:
- Industrial consultants who perform risk assessments for different industries. The tool allows them to generate more accurate assessments quickly and efficiently.
- Insurance companies and brokers that need to evaluate the risks associated with certain facilities. AW-OZ can help these companies better understand the explosion risks of their clients’ operations.
- Design officers who must ensure that new equipment or processing lines meet safety standards. AW-OZ can assist them in making informed decisions about equipment design and installation.
- Equipment manufacturers who need to adapt their products to meet explosion safety regulations. The tool can help manufacturers design safer equipment from the ground up.
- Production companies in industries such as food processing, woodworking, and chemical manufacturing, where combustible dust is a known hazard. These companies can use the tool to assess the risks of their existing equipment and make necessary safety upgrades.
Dr. Wolff stressed that AW-OZ is not a “do-it-yourself” tool. It is intended to be used by professionals with a deep understanding of explosion risks. While the tool simplifies the risk assessment process, users are encouraged to work with specialists to ensure that the recommendations provided are appropriate for their specific situation.
How Does AW-OZ Work?
The AW-OZ tool works by gathering specific data about the process being assessed and using that information to calculate a hazard value. The inputs required for the assessment include:
- The properties of the combustible dust (e.g., minimum ignition energy, lower explosion limit).
- The dimensions of the equipment (e.g., volume, height, length).
- The operational conditions (e.g., continuous or batch operation, presence of dust collection systems).
- The presence of potential ignition sources (e.g., electrostatic discharges, hot surfaces).
Once the data is entered into the tool, AW-OZ uses this information to determine the level of explosion risk. The tool assigns a hazard value based on the input data and categorizes it into one of four risk levels. After the risk level is determined, AW-OZ provides recommendations for appropriate explosion protection measures. These recommendations may include suppression systems, explosion venting, or other protective measures tailored to the specific equipment and process.
Dr. Wolff explained that AW-OZ is designed to be flexible. It can be used for both existing equipment and new installations, making it a versatile tool for any industry handling combustible dust.
Examples of AW-OZ in Use
Although Dr. Wolff was unable to provide specific case studies due to confidentiality agreements with clients, he did mention that AW-OZ is already being used as a standard tool by his team during ATEX audits in various industries. The tool has been successfully applied in industries ranging from food processing to woodworking, helping companies assess and mitigate the risks associated with combustible dust.
Dr. Wolff also plans to present several case studies at upcoming conferences, including the Hazard Conference in the UK and the Loss Prevention Conference in Bologna, Italy, both in 2025. These case studies will provide a closer look at how AW-OZ is being used in real-world scenarios to improve safety and compliance.
Cautions When Using Quantitative Risk Assessments
While AW-OZ is a powerful tool, Dr. Wolff emphasized the importance of using it correctly. The results generated by the tool are considered preliminary, and users are encouraged to consult with experts to review the findings. This is because the tool relies on general process data and may not account for every specific variable in complex systems.
Dr. Wolff cautioned against viewing AW-OZ as a “set-it-and-forget-it” solution. The tool provides a solid foundation for explosion risk assessments, but human oversight is still necessary to ensure that the right protection systems are implemented. Users should be cautious when interpreting the results and ensure that the recommended safety measures are appropriate for their specific facility.
How to Access AW-OZ
AW-OZ is currently available for testing, though it is only offered in Polish at the moment. Dr. Wolff’s team is working on translating the tool into English, and the new version will be available soon. Interested parties can contact Dr. Wolff directly at [email protected] to request access to the tool. The tool is being offered to potential partners for evaluation and feedback, with the aim of expanding its use across industries.
Conclusion
AW-OZ represents a significant advancement in the field of explosion risk assessment. By using process data and equipment specifications, the tool offers a more objective and reliable way to evaluate the hazards posed by combustible dust. However, AW-OZ is not a standalone solution. Experts should be involved in reviewing the results and ensuring that the recommended explosion protection measures are tailored to the specific risks present at a facility. As AW-OZ continues to evolve, it promises to become an indispensable tool for industries seeking to improve safety and compliance in bulk material processing.
If you would like to discuss further, leave your thoughts in the comments section below. You can also reach Dr. Andrezj Wolff directly:
Website: https://www.grupa-wolff.eu/
LinkedIn: https://www.linkedin.com/in/andrzej-wolff-224bb014a/
Email: [email protected]
If you have questions about the contents of this or any other podcast episode, you can go to our ‘Questions from the Community’ page and submit a text message or video recording. We will then bring someone on to answer these questions in a future episode.
Resources mentioned
The resources mentioned in this episode are listed below.
Dust Safety Science
Combustible Dust Incident Database
Dust Safety Science Podcast
Questions from the Community
Companies
Grupa Wolff
Standards
NFPA 654
Download the episode
DSS285: Introducing AW-OZ – a Web-Based Risk Assessment Solution with Dr. Andrezj Wolff
