Wood Destroying Organism (WDO) Home Inspection 2025 – 400 Free Practice Questions to Pass the Exam

The term that accurately describes the presence of an unwanted substance in or on a structure is contamination. This term is commonly used in various fields, including environmental science and home inspection, to indicate that a material has been introduced where it is not wanted, potentially causing harm or deterioration.

Contamination may refer specifically to substances such as mold, pests, or any hazardous materials that compromise the integrity of the structure or pose health risks to the occupants. Identifying contamination is crucial in home inspections, particularly regarding wood-destroying organisms, since they can lead to significant structural damage and health issues if not addressed promptly.

In contrast, the other terms do not convey the exact nature of unwanted substances in a structure. Intrusion typically refers to an unexpected or unwelcome entry, often used in a legal or physical context rather than specifically indicating an unwanted substance. Infiltration suggests the gradual movement of substances, often air or moisture, into a space, which doesn’t explicitly indicate contamination. Exclusion refers to the act of preventing entry or presence, which is a proactive measure rather than describing a current state of being contaminated.