Minimum number of composite dust samples when using a composite approach?

Minimum number of composite dust samples when using a composite approach?

• A. 2
• B. 3
• C. 4
• D. 5

Answer: (B)

Composite sampling means pooling several wipe samples into one laboratory analysis to save time and cost. To get a reliable picture of dust contamination across a space, you need enough composites to represent different areas where contamination could vary. Using too few composites risks missing hotspots or variations between locations. Three composites provide a basic level of spatial coverage: it’s enough to capture variation across different zones (for example, multiple floor areas or a high-traffic spot plus another area) without overcomplicating the sampling. You can add more composites if the area is larger or more variable, but three is the standard minimum.

Composite sampling means pooling several wipe samples into one laboratory analysis to save time and cost. To get a reliable picture of dust contamination across a space, you need enough composites to represent different areas where contamination could vary. Using too few composites risks missing hotspots or variations between locations. Three composites provide a basic level of spatial coverage: it’s enough to capture variation across different zones (for example, multiple floor areas or a high-traffic spot plus another area) without overcomplicating the sampling. You can add more composites if the area is larger or more variable, but three is the standard minimum.