An Asbestos Fiber Detection Technique Utilizing Image Processing Based on Dispersion Color

Abstract

In an asbestos qualitative analysis, the major methods are X-ray diffraction analysis and visual observation by operators using a microscope. In particular, a major method of visual evaluation is dispersion staining. In the usual visual observation process, the operators check the asbestos fibers in the view of the microscope and count the number of asbestos fibers. The method presented here attempts to detect asbestos fibers in the images taken by a microscope. The dispersion staining method identifies asbestos fibers with color dispersion from an immersion liquid combined with polarization. The presented method employs color changes of asbestos fibers associated with polarization. Specifically, candidate asbestos fibers are identified using the changes of dispersion colors and also position-matching between two images. The performance of the method has been evaluated by comparing its results with the results obtained by a human expert.

Keywords:

• asbestos
• dispersion color
• image processing
• qualitative analysis

Acknowledgments

The authors give thanks to Takeda-Rika Co. and Japan Testing Center for Construction Materials (JTCCM) for their kind contribution to this research. This research was supported by the research program of Ministry of the Environment of Japan (Nos. K1920, K2061).