The correct answer is A. 0.001 mg/m3.
The threshold limit value (TLV) is the concentration of a substance in the air that is believed to be safe for most workers to be exposed to for an 8-hour workday, 40-hour workweek. The TLV is set by the American Conference of Governmental Industrial Hygienists (ACGIH).
Copper is a naturally occurring element that is found in the earth’s crust. It is also used in a variety of products, including pipes, wires, and coins. Copper can be a health hazard if it is inhaled or ingested. Exposure to high levels of copper can
cause a variety of health problems, including respiratory problems, kidney problems, and liver problems.The TLV for copper in the atmospheric air is 0.001 mg/m3. This means that the average worker can be exposed to up to 0.001 milligrams of copper per cubic meter of air for an 8-hour workday, 40-hour workweek without experiencing any
adverse health effects.The other options are incorrect because they are higher than the TLV for copper in the atmospheric air.