CDPH Lead Inspector/Assessor California State Practice Exam

Which type of lead sampling can effectively measure levels of lead in water?

1. Grab sample

2. Composite sample

3. Bulk sample

4. Filtered sample

The correct answer is: Grab sample

The most effective method for measuring lead levels in water is through a grab sample. This sampling technique involves collecting a single, specific sample at a particular moment in time, which allows for the immediate analysis of lead concentrations in water. Grab sampling is particularly useful because it can provide a snapshot of lead concentrations that may fluctuate based on various factors, such as water flow, time of day, and the presence of lead-containing plumbing. In contrast, composite samples involve combining multiple samples over time or different locations, which may dilute lead concentrations and not accurately reflect the water's quality at any given moment. Bulk samples pertain to materials rather than liquids and are not applicable to water sampling. Filtered samples involve removing particulate matter from the water before analysis, which can also lead to variations in the measured lead levels if the lead is attached to particles. Therefore, grab samples are the most appropriate choice for effectively measuring lead concentrations in water.