What are a few of the methods that can be used to collect samples of gaseous vapors?

The use of commercially available sampling devices is a crucial method for collecting samples of gaseous vapors. These devices are specifically designed to capture and analyze various gases and vapors in the environment, ensuring accurate and reliable results. They typically include tools like canisters, sorbent tubes, and gas sampling bags that can effectively collect vapor samples for further laboratory analysis. This specialized equipment allows for the identification and quantification of specific compounds, which is essential in fire investigation to determine the presence of accelerants or other hazardous materials.

In comparison, while human breath analysis can provide information on specific gases exhaled by individuals, it is not a primary method for collecting vapors in a fire investigation context. Visual inspection and water testing also do not pertain to the direct collection of gaseous samples but rather involve examining physical evidence or testing water for contaminants. Thus, the correct answer emphasizes the use of specialized equipment to ensure accurate data collection in the field of fire investigation.