What term describes chemicals used to cover unpleasant smells in wastewater facilities?

• A. Odor Masking Products
• B. Masking agents
• C. Fragrance additives
• D. Odor control chemicals

Answer: (B)

Masking agents describe chemicals used to cover unpleasant smells by adding a fragrance that overpowers the odor. In wastewater facilities, these compounds aim to make the air more acceptable by introducing a scent that the human nose detects more strongly than the malodors, rather than removing the odor molecules themselves. This is why masking agents is the best term: it precisely conveys the purpose of covering odors rather than eliminating them. Other terms are broader or less precise—odor control chemicals refer to substances that actually neutralize or remove odors, fragrance additives describe scents added for consumer-like fragrance, and odor masking products is a more informal phrasing of the same idea but not as established in technical terminology.