Ventilation and Filtration in Postal Service Facilities

The U.S. Postal Service owns over 8,400 facilities where it provides services, which includes maintaining proper ventilation and filtration in these facilities to ensure they are clean and safe. Ventilation and filtration are often provided by heating, ventilation, and air conditioning systems in a facility. Industry standards recommend minimum ventilation rates and inspection and maintenance activities.Our objective was to assess Postal Service efforts to ensure proper ventilation and filtration in facilities and identify opportunities for improvement. For this audit, we statistically sampled 193 Postal Service-owned retail and delivery facilities with an interior size ranging from 1,000 to 100,000 square feet from a universe of 6,709 facilities.