Which of the following are the two methods of air sampling?

The two methods of air sampling in the context of asbestos monitoring are PCM (Phase Contrast Microscopy) and TEM (Transmission Electron Microscopy). PCM is widely used for analyzing airborne asbestos fibers due to its ability to provide rapid results and a reasonable estimation of asbestos fiber concentration in air. It identifies fibers based on their optical characteristics and operates under specific sampling conditions that are designed to capture fibers effectively.

TEM, on the other hand, is a more advanced microscopy technique that can provide a detailed analysis of the size, morphology, and type of asbestos fibers present in an air sample. It is particularly useful for quantifying and identifying different types of asbestos, which is crucial in risk assessment and regulatory compliance.

Both methods offer different advantages; PCM is more widely used for routine monitoring, while TEM is employed when a more thorough identification is necessary or when more precise measurements are required. The combination of these two methodologies provides a comprehensive approach to understanding airborne asbestos contamination, making them the correct answer in this context.

The other options include methods like NIOSH and AHERA, which refer to organizations and regulations rather than direct methods of air sampling. PLM (Polarized Light Microscopy) is a method used to analyze solid samples for asbestos content, but it does not pert