Fresh Air & IAQ Systems

Ventilation moves air in/out of spaces for air exchange. Fresh air treatment conditions outdoor air (filters, heats/cools, dehumidifies) before introduction to maintain indoor air quality, comfort, and hygiene standards.

ASHRAE Standard 62.1 recommends 5-20 CFM per person depending on space type. Offices typically require 5 CFM/person, while restaurants need 7.5 CFM/person. Healthcare and laboratory spaces have higher requirements.

Key components include outdoor air intake with weather protection, multi-stage filtration (pre-filters, bag filters, HEPA/ULPA for critical applications), cooling/heating coils, humidification/dehumidification, fans, controls, and energy recovery devices.

Energy Recovery Ventilators (ERVs) or Heat Recovery Ventilators (HRVs) transfer energy between exhaust and fresh air streams, reducing heating/cooling loads, improving efficiency by 50-80%, and maintaining humidity control.

Pre-filters: 3-6 months, Bag filters: 6-12 months, HEPA filters: 1-3 years depending on usage and air quality. Pressure drop monitoring provides the most accurate replacement timing.

Common pollutants include particulate matter (PM2.5, PM10), volatile organic compounds (VOCs), carbon dioxide, carbon monoxide, allergens, mold spores, bacteria, viruses, and odors from building materials/occupants.

TFA (Treated Fresh Air) units condition outdoor air to neutral conditions before mixing with return air. PAU (Primary Air Handling Units) handle 100% outdoor air with full conditioning (heating/cooling/dehumidification) for spaces requiring dedicated fresh air supply.

Positive pressure prevents unfiltered outdoor air infiltration. Negative pressure contains contaminants (labs, isolation rooms). Neutral pressure maintains balance. Proper pressurization is critical for infection control, contamination prevention, and energy efficiency.

Key standards include ASHRAE 62.1 (ventilation), 55 (thermal comfort), 170 (healthcare), ISO 16890 (air filters), WHO air quality guidelines, LEED/IGBC green building standards, and local building codes.

Yes, through adding dedicated fresh air units, upgrading filtration (MERV 13+), adding UV-C germicidal irradiation, installing energy recovery, improving controls, and enhancing duct cleaning/maintenance protocols.

ROI includes reduced absenteeism (8-12% productivity gain), lower healthcare costs, decreased energy consumption through recovery systems, extended equipment life, and improved occupant satisfaction/retention.

Integration includes CO2-based demand control ventilation, pressure monitoring/alarms, filter status monitoring, energy optimization, remote access, data logging for compliance, and coordination with fire/safety systems.