HUD Guidelines for XRF testing on single-family housing require at least how many locations per testing combination?

HUD Guidelines for XRF testing on single-family housing require at least how many locations per testing combination?

• A. 2 locations per testing combination
• B. 1 location per testing combination, except interior and exterior walls; 4 readings, one on each wall.
• C. 5 locations per testing combination
• D. 3 locations per testing combination

Answer: (B)

When planning XRF testing, you want enough data points to capture how lead-based paint can vary from surface to surface. HUD’s guidelines for single-family housing specify one reading per testing combination for most surfaces, but interior and exterior walls need more coverage because they often show greater variability in paint layers and coating conditions. Therefore, take four readings for walls—one on each wall—to ensure you’re sampling across the different surfaces. This approach helps prevent misclassifying the presence or absence of lead-based paint based on a single spot. The rule emphasizes one location per testing combination in general, with four readings specifically on walls.

When planning XRF testing, you want enough data points to capture how lead-based paint can vary from surface to surface. HUD’s guidelines for single-family housing specify one reading per testing combination for most surfaces, but interior and exterior walls need more coverage because they often show greater variability in paint layers and coating conditions. Therefore, take four readings for walls—one on each wall—to ensure you’re sampling across the different surfaces. This approach helps prevent misclassifying the presence or absence of lead-based paint based on a single spot. The rule emphasizes one location per testing combination in general, with four readings specifically on walls.