Environmental monitoring in an animal facility includes which sample types?

• A. Air.
• B. Water.
• C. Surface.
• D. Air, water, and surface samples.

Answer: (D)

In environmental monitoring, you want to capture contamination across the different environments that animals and staff interact with. Sampling air, water, and surfaces together gives a complete picture of cleanliness and potential exposure routes. Air sampling detects aerosols and airborne microorganisms that could be inhaled or spread through the facility. Water sampling checks the quality of drinking and process water, as well as water used for cage cleaning and equipment, to catch microbial contamination or endotoxins. Surface sampling assesses microbes on cages, benches, equipment, and other high-touch areas where organisms can persist and be transferred.

Relying on just one type would miss other routes of contamination—for example, air testing alone might not reveal waterborne or surface contamination, while surface testing wouldn’t detect airborne pathogens or waterborne organisms. Therefore, including air, water, and surface samples provides the most thorough environmental monitoring.