Which method is commonly used to analyze samples for the presence of asbestos?

The method commonly used to analyze samples for the presence of asbestos is polarized light microscopy (PLM). This technique involves examining samples under a polarized light microscope, which allows for the identification of asbestos fibers based on their optical characteristics. PLM is particularly effective for distinguishing asbestos from other materials, as the unique refractive indices and birefringence properties of asbestos fibers can be observed when polarized light passes through them.

While other analytical methods, such as gas chromatography, high-performance liquid chromatography, and nuclear magnetic resonance, are useful in various chemical analyses, they are not suitable for identifying asbestos. These methods either focus on volatile compounds or rely on magnetic properties that do not provide the specific information needed to determine the presence of asbestos fibers. Thus, PLM is the established standard for asbestos analysis, making it the correct choice in this context.