New York State Asbestos Investigator Practice Exam

What is the method used for analyzing air samples in asbestos investigation?

1. Scanning electron microscopy

2. Phase contrast microscopy

3. Gas chromatography

4. Mass spectrometry

The correct answer is: Phase contrast microscopy

Phase contrast microscopy is a widely recognized method for analyzing air samples in asbestos investigation due to its ability to provide clear visual differentiation of asbestos fibers from other particles present in the sample. This technique enhances the contrast of transparent and colorless specimens, like asbestos fibers, allowing for detailed observation and assessment. In asbestos air sampling, the collected samples are often filtered through a membrane filter, and phase contrast microscopy allows investigators to examine the fibers directly on the filter. This method is effective for quantifying the number of asbestos fibers and determining their types, which is crucial for assessing potential health risks and compliance with safety regulations. While scanning electron microscopy is also used for detailed analysis, it is more complex and often reserved for identifying specific types of asbestos. Gas chromatography and mass spectrometry are methodologies more applicable to chemical analysis rather than direct fiber counting and identification in air samples, making them less suitable for this type of investigation.