What must be established before sampling a hazardous material?

Before sampling a hazardous material, it is essential to establish the method of sampling because this determines how the sampling will be conducted in a safe and effective manner. The chosen method ensures that samples collected are representative of the hazardous material, allowing for accurate analysis and assessment of the situation. Having a clear protocol for sampling helps minimize risks involved during the process and ensures that the data gathered is reliable for subsequent decision-making.

In addition to ensuring safety and accuracy in sampling, an established method will also facilitate a systematic approach that adheres to regulations and best practices in hazardous material response. Other choices, such as having a list of potential hazards or assessing field experience, may be important in the broader context of incident response, but they do not directly guide the actual sampling process as clearly as the method itself does.