Loading is defined as a measure of what?

Loading is defined as a measure of what?

• A. milligrams per square meter
• B. micrograms of lead per square foot of surface area
• C. grams per square inch
• D. micrograms per gram

Answer: (B)

Loading is about how much lead is present on a surface relative to the area of that surface. It measures the contaminant mass per unit area, which helps assess exposure risk from surfaces people touch or dust from that surface can settle on. The standard unit used is micrograms of lead per square foot of surface area, not per gram or per square inch, and not as a concentration per mass. For example, if a surface contains 100 micrograms of lead spread over 4 square feet, the loading would be 25 micrograms per square foot. This per-area measure is why the correct choice uses micrograms per square foot of surface area.

Loading is about how much lead is present on a surface relative to the area of that surface. It measures the contaminant mass per unit area, which helps assess exposure risk from surfaces people touch or dust from that surface can settle on. The standard unit used is micrograms of lead per square foot of surface area, not per gram or per square inch, and not as a concentration per mass. For example, if a surface contains 100 micrograms of lead spread over 4 square feet, the loading would be 25 micrograms per square foot. This per-area measure is why the correct choice uses micrograms per square foot of surface area.