What is the ILAR Guide recommended air changes per hour (ACH) range?

What is the ILAR Guide recommended air changes per hour (ACH) range?

• A. 5-10
• B. 10-15
• C. 15-20
• D. 20-25

Answer: (B)

Ventilation and how often room air is changed are key to keeping the animal housing environment clean and comfortable. The ILAR Guide for the Care and Use of Laboratory Animals sets a typical range of ten to fifteen air changes per hour for general animal rooms. This amount provides enough dilution of odors, dust, and airborne contaminants while balancing energy use and stable temperature and humidity. Higher ranges, like fifteen to twenty or twenty to twenty-five, are usually reserved for areas with greater contamination risk or isolation needs, whereas lower ranges would not reliably maintain air quality in standard housing.

Ventilation and how often room air is changed are key to keeping the animal housing environment clean and comfortable. The ILAR Guide for the Care and Use of Laboratory Animals sets a typical range of ten to fifteen air changes per hour for general animal rooms. This amount provides enough dilution of odors, dust, and airborne contaminants while balancing energy use and stable temperature and humidity. Higher ranges, like fifteen to twenty or twenty to twenty-five, are usually reserved for areas with greater contamination risk or isolation needs, whereas lower ranges would not reliably maintain air quality in standard housing.