Some dairy facilities utilize one or more odor reduction technologies to reduce odor emission such as biofilters and/or diet manipulation. The odor abatement effectiveness factor (A_E) is used to account for the reduction of odor emission from buildings. The allowable reduction of odor emission ranges from 0 to 70%.

The odor abatement factor for outside liquid manure storage A_S is used to characterize the reduction in odor emission as compared to open liquid storage. As with the reduction of odor from buildings, some dairy facilities utilize one or more odor reduction technologies for outside manure storages. Surface aeration of anaerobic lagoons, biogas generators, and impermeable manure storage covers are examples of odor reducing technology.

Recommendations of odor reduction (in %) for some common dairy odor abatement technologies are given:

Barn Technology	Reduction (%)
Biofilter	86