What is true regarding tarping in fumigation regarding thickness?

The assertion about tarping in fumigation being independent of permeability is indeed correct. When considering the effective use of tarps for fumigation, permeability refers to how easily gases can pass through the material of the tarp. While the thickness of the tarp can influence its durability and potential for leakage, the effectiveness of fumigation relies significantly on the chemical properties of the fumigant and the conditions of the fumigation environment rather than just the thickness of the tarp itself.

Choosing a tarp with the right thickness is important for structural integrity and preventing tears or breaches, but a thicker tarp does not necessarily equate to better fumigant retention if it has high permeability. The characteristics of the fumigant and the application method are the most crucial factors in determining the overall effectiveness of the fumigation process.

In contrast, the other options indicate factors that are not primarily focused on the essential nature of thickness. The chemical used, density, and practices such as doubling the tarp may influence the fumigation process but are not directly tied to the fundamental consideration of thickness in tarping practices. Therefore, the focus on permeability as a separate concern validates the correctness of the choice regarding its independence from thickness in the context of fumigation.