Let in Some Air
For many commercial buildings constructed since the energy crisis of the ’70s, the drive to build-in energy efficiency had the unintended consequence of creating “sick building syndrome,” resulting in health problems and reduced productivity in the workforce.
Efficient and cost-effective heating and air conditioning was seen as requiring tight control of air coming into the building from the outside which was either too hot or too cold, depending on the season. Rather than have the heating/air conditioning systems spend more energy treating the incoming ambient air to thermally match the air inside, architects and HVAC system designers made buildings increasingly air tight. The common practice was to recycle the air inside a building many times over.
The drastic reduction of ambient air flow used for renewal and ventilation soon had workers complaining of headaches, grogginess and increasingly severe illnesses. Employers saw decreased production and increased absenteeism due to a rise in pollutants and germs floating in the workplace air.
Your heating, ventilation and air conditioning (HVAC) system needs to give you and your workers fresh air. Many commercial building in the U.S. have air exchange rates ranging from 0.29 to 1.73 changes per hour. Office buildings, however, should have exchange rates of 6 to 10 changes per hour. Other recommended air change rates per hour (ACH) include:
- Restaurants, 8- 12 ACH
- Factories and workshops, 8-10 ACH
- Foundries, 15-30 ACH
- Bakeries and Commercial Kitchens, 20-30 ACH
Actual rates needed, however, vary upon conditions in the building and how many people are in it. Pollutants can come from office equipment, machinery and even personal hygiene products.
High exhaust fans such as those used in commercial kitchens also require special make-up air units that directly replace the air being evacuated or risk having the exhaust fans pull in fumes from chimney backdrafts, water heaters and other unwanted sources, replacing the air with carbon monoxide and even volatile gases.
Even if your HVAC system is capable of changing the air inside at a high enough rate, you also need the ventilation to flow adequately and not leave deadzones where the air doesn’t circulate. Misplaced vents that are too close to each other or that don’t direct the flow in one direction create turbulence in the space where the stale air never leaves. Office cubicles that don’t have open space near the floor for ventilation can also trap stale air around the worker.
Just pulling in air from the outside, however, may not be the answer. Air in some locations can be heavily polluted, or even worse, be too near a neighboring building’s exhaust vents spewing out concentrated pollutants that instead of dissipating get sucked right into your ventilation system.
AbsolutAire’s design and installation of industrial and commercial HV AC systems starts with the premise that almost every building or enclosure requires some type of ventilation to prevent the buildup of harmful gases and contaminants. Fresh air needs to replace stale air. New air must replace exhausted air. Yet the air brought into a building, depending on the climate and season, must be tempered to satisfy ventilation requirements, and adequately filtered to prevent injecting outside pollutants and contaminants into your indoor environment.
To those ends “total air management” is at the heart of AbsolutAire’s engineering design strategy to optimize indoor air quality by delivering cost effective, environmentally sensitive, reliable, and durable customer-driven solutions.
Pure and Simple: AbsolutAire has an absolute commitment to providing its customers with total value in direct fired make up air, indirect fired make up air and heating and ventilating systems. This means applying the best available technology to preserve precious resources, slash heating and ventilation costs, and shrink our environmental footprint.