How should dust composite samples be calculated according to the lead-based paint standard?

The calculation of dust composite samples according to the lead-based paint standard involves dividing the total concentration of lead by the number of sub-samples taken. This method is essential for accurately assessing the average lead concentration in dust, which can inform risk assessments and subsequent actions regarding lead exposure.

Dividing by the number of sub-samples provides a more precise representation of the lead levels in a specific area, allowing for a comprehensive understanding of potential lead exposure risks. This approach acknowledges the variability that can exist in dust samples collected from different locations within a property or environment.

Using this method ensures that all collected samples are considered, thus providing a more representative average that can aid in making decisions regarding lead safety and remediation actions. Other methods, such as focusing solely on the heaviest sample or just adding samples together, would not provide an accurate assessment of lead exposure and could lead to either underestimating or overestimating risks.