Which sampling method is commonly associated with analyzing bulk samples?

The method commonly associated with analyzing bulk samples is direct microscopic examination. This technique involves taking a small portion of the bulk material, such as drywall, wood, or other substances that may contain mold, and examining it under a microscope. This allows for the identification and characterization of mold spores and other microbial structures directly from the sample.

Direct microscopic examination is particularly useful because it provides immediate insights regarding the presence of mold, the types of spores present, and their potential concentrations in the material being analyzed. This method is often employed in laboratory settings where a detailed analysis of the bulk material's composition is required, making it a standard practice in mold assessments.

In contrast, the other sampling methods listed are either focused on different types of analysis or are not specifically intended for bulk samples. For instance, vacuum sampling typically involves collecting airborne microscopic particles, while air sampling measures the concentration of mold spores in the atmosphere. Swabbing is a surface sampling technique designed to collect visible residues or spores from surfaces rather than analyzing the bulk material itself.