Environmental Protection Agency (EPA) Lead Risk Assessor Practice Exam

To ensure accurate measurements, what aspect of dust wipe criteria should differ?

1. Volume of dust collected

2. Type of surface sampled

3. Height of the sampling position

4. Model of wipe used

The correct answer is: Type of surface sampled

The correct aspect of dust wipe criteria that should differ to ensure accurate measurements is the type of surface sampled. Different surfaces may have vastly different characteristics that affect how lead dust adheres and is collected. For instance, a carpeted surface may trap particles differently compared to a hardwood floor, leading to discrepancies in lead concentration measurements. By varying the type of surface sampled, a more comprehensive understanding of lead presence and potential exposure risks can be achieved, leading to more effective risk assessments. The other aspects, while they may influence measurement in some way, do not provide as critical a factor for accuracy in the context of different dust wipe criteria. The volume of dust collected is important for quantifying lead presence but does not directly relate to the effectiveness of different surface types in capturing lead particles. The height of the sampling position can help standardize collections but does not change the fundamental characteristics of the surface sampled. Lastly, the model of wipe used may affect the efficiency of dust collection, but changing the surface type has a more direct impact on understanding lead exposure in various environments.