Fresh Air in Animal Facilities
In the ever-changing and fast-paced environment of animal sheltering and animal welfare, it is essential to reflect on where the animal care industry was in the past and where it is headed in the future in terms of animal care facility engineering and design. Many aspects of building design have changed drastically in the past 50 years, particularly for animal shelters and rescues. Here, we will discuss fresh air and ventilation in animal care facilities.
Ventilation in animal facilities (like animal shelters, veterinary hospitals, and boarding facilities) is critical to animal health. Six aspects that affect ventilation include:
Fresh Air Dilution
Air Distribution
Mechanical Zoning
Exhaust Locations
Air Filtration
Dehumidification
Past Engineering Considerations on Ventilation in Animal Facilities
Historically, air distribution was an agricultural airflow model with minimal distribution and airflow exhaust from a single location.
Guidelines relied on extremely high rates of outside air throughout the entire building. Fresh air changes in a building above 10 ACH (air changes per hour) are costly to heat and cool. (It's important to note that these dilution levels are still appropriate for highly infectious disease conditions but excessive and expensive for otherwise healthy animals and human areas.)
Guidelines had no reference to the other essential aspects of ventilation other than outside air.
Recommendations originated in the 1963 Guide for the Care and Use of Laboratory Animals, now in its 8th edition.
Spaces were not properly treated for their humid or cool, damp climates, which brought tremendous moisture into the building.
Current Engineering Recommendations for Fresh Air and Ventilation in Animal Facilities
Several significant changes have occurred in animal facility engineering:
Industrial ventilation guidelines (a perfect application for animal care facilities) are available for precise air distribution and exhaust.
HVAC zoning permits specific ventilation rates for particular functions.
Current ASHRAE standards target specific amounts of fresh air for each veterinary area.
Advanced ultraviolet germicidal irradiation systems are available specifically for animal health and can be more effective than fresh air dilution for specific pathogens.
Treating pathogens with advanced surface cleaning chemicals specifically for animal health is easier, faster, and more effective than treating them in the air.
Advanced animal waste removal systems are available specifically for animal health.
Humidity and surface-borne pathogen growth are well understood today.
Humidity should be below 70% RH - and that is very difficult with excessive ACH.
Energy Codes require substantial air treatment and energy recovery for outside air systems.
Importance of Adopting the Current Engineering Recommendations in Animal Facilities
Why these engineering changes are essential:
The cost of properly designed mechanical systems today for animal care is over $50 per square foot.
In a modern, well-insulated building with specific, targeted fresh air dilution, heating, cooling, and dehumidification costs represent more than 80% of the HVAC utility costs.
High ACH throughout the entire building will more than triple the cost of equipment and utilities.
Energy and Mechanical Codes are increasingly limiting fresh air dilution to specific quantities.
Targeted fresh air dilution with multiple, smaller zones is less expensive and far more effective in containing pathogens.
Fresh air exchange is a critical aspect of indoor air quality, but without correctly engineering the other ventilation aspects, the fresh air may have limited effectiveness.
The understanding of mechanical and HVAC requirements in animal sheltering and welfare is one of the many aspects in the engineering and design of these building types that has grown dramatically over the years and continues to evolve.
Improve Ventilation in Your Animal Care Facility
Contact the Design Learned team of building experts to learn more about how engineering considerations have changed over the years. We'd love to discuss updating your current facility or supporting your new building development. Call us at 860-889-7078 or schedule a consultation online to discuss this further.