In this article, we aim to highlight a different aspect of our consultancy work. At Delft Solids Solutions, we regularly provide technical consultancy for legal cases. Throughout this year, we will share several remarkable cases that we have been a part of, showcasing the fascinating aspects of powder technology and material science.

Our expertise spans a variety of industries, including pharmaceuticals, chemicals, petrochemicals, automotive, food and feed, cosmetics, paints and coatings, and building materials. Given this broad experience, we were approached to offer clarity in the following legal case. Our insights aim to assist legal professionals in navigating the complexities associated with material properties and their implications in various contexts.

A Belgian museum, which curates a significant collection of rare and valuable art pieces, discovered unexplainable dust on their artworks. This contamination raised concerns, especially since a demolition project was underway nearby. Although the contractor implemented precautions to limit dust exposure, questions emerged regarding the source of the contamination.

The critical inquiry was whether the dust from the building site was responsible for affecting the paintings. Our technical consultancy aimed to investigate the composition and characteristics of the dust to determine its origin and potential impact on the museum’s valuable collection. By conducting a thorough analysis, we sought to provide clarity on this issue and help the museum understand the extent of the contamination and the necessary steps for remediation.

To examine this issue, we undertook several key steps. First, we determined the physico-chemical properties of the material found at the demolition site. We investigated both the size and chemical composition of the dust particles.

Next, we encountered challenges when extracting a suitable and representative amount of dust from the HVAC filters. A mechanical dry procedure proved inadequate, as small pieces of the HVAC filter itself contaminated the dust samples. Consequently, we employed a material extraction procedure that utilized ethanol to flush the filters. This method allowed the ethanol to gently release the particles from the filter material, collecting both the ethanol and the intended dust particles.

After obtaining the suspension of ethanol with dust particles, we dried the mixture since the XRF (X-ray fluorescence) technique requires dry powders for analysis. We noted that the reference sample collected from the demolition site exhibited significantly different particle sizes and colors. To ensure consistency, we first milled this sample in a ball mill to homogenize it, making it more suitable for accurate XRF analysis.

We found that the elemental composition of the concrete dust closely matches the anticipated composition of concrete. Key components include calcium and iron, both derived from cement, along with silicon from sand. Notably, we also detected sulfur in both samples. This presence may be explained by sulfur’s use as an additive in concrete to enhance corrosion resistance, which could account for the significant amount of sulfur observed.

Additionally, sulfur is less commonly found in a variety of materials compared to silicon. This observation further supports the conclusion that both samples share a similar origin.

Delft Solids Solutions has provided a wealth of content over the years, primarily focusing on the physical properties of powders and granules, as well as related technologies and techniques. With over 40 years of experience, we specialize in porosity and surface area of solids, particle size and shape, composition, and a comprehensive understanding of solids behavior.

Drawing on this extensive expertise, we offer a diverse range of unique services. These include researching materials’ properties, developing new techniques, methodologies, and equipment, and conducting innovative research projects for materials development. Additionally, we provide consultancy services in powder technology to help our clients navigate their specific challenges effectively. Our commitment to advancing knowledge in these areas ensures that we remain a valuable partner in the field of material science.