Case Study: Paint Overspray

Overspray is the application of airborne particulate material onto an unintended surface. The overspray could potentially cause damage to the surface, especially if it is not easily removable. In this case study we were asked to investigate paint overspray and compare it to a possible source. We also analyze adhesives and coatings and can provide our clients with information about the chemical composition, structure and size of the overspray particulate.

THE PROBLEM: White specks resembling dried paint droplets were observed on the exterior surfaces of several vehicles parked in the same parking lot. We were asked to determine if the white specks were overspray from paint being applied in the vicinity of the cars.

THE ANALYSES: Samples of the white specks that were collected off the surface of the vehicles and the suspected paint were analyzed using polarized light microscopy (PLM), scanning electron microscopy (SEM) coupled with energy dispersive x-ray spectroscopy (EDS), and Fourier Transform Infrared Spectroscopy (FTIR). The use of various instruments allowed us to determine if the material on the cars was consistent with paint by comparing the two visually and chemically. The white specks from the cars and samples of the suspected paint were primarily silicon (Si) and titanium (Ti). EDS spectra of these results are shown on the right in Figures 1 and 2, respectively. Figure 3 shows FTIR spectra from the white specks on cars (top) and from the paint (bottom).

THE OUTCOME: Comparison of the composition of the white specks on the cars with the reference paint indicates the white specks are an overspray consistent with the suspected paint.

If you are concerned about overspray on cars, boats, buildings or other surfaces, we can help investigate the possible source. If you have an airborne product you would like to characterize, we can provide information about its composition, structure and particulate size.

Contact us at 770-662-8509 or info@mvainc.com.