According to the U.S. Environmental Protection Agency (EPA), the growing proliferation of chemical pollutants in consumer and commercial products, the tendency toward tighter building envelopes and reduced ventilation to save energy, and pressures to defer maintenance and other building services to reduce costs have fostered IAQ problems in many buildings. As a result, more building occupants are complaining of odors, stale and stuffy air, and symptoms of illness or discomfort.

But there is no reason why this should be happening, as numerous solutions are available to mitigate most IAQ problems.


Commercial IAQ problems often stem from poorly maintained HVAC systems, which can be ideal breeding grounds for microbial buildup in cooling coils, drain pans, and duct surfaces, said Dan Jones, president of UV Resources. “For this reason, when contractors are trying to isolate an IAQ problem, they should always check a building’s central air conditioning system first — particularly in hospitals, which are seeing a rise in antibiotic-resistant superbugs. Preventing these hospital-acquired infections (HAIs) from taking root is a priority.”

One way to prevent these problems from arising is to install ultraviolet-C (UV-C) systems that use UV-C’s germicidal energy to inactivate virtually any airborne pathogen, said Jones. “For example, our RLM Xtreme UV-C lamp system can be applied to new equipment to maintain specified coil efficiency and performance as well as be retrofitted into existing HVAC systems to address degraded heat transfer and pressure drop due to fouled coils. By keeping coils clean year-round, the HVAC system remains energy efficient and can deliver clean air at the desired set point temperature.”

While building owners and managers tend to be aware of IAQ issues, they are also concerned about the costs associated with IAQ products as well as the claims being made by manufacturers. “Contractors should emphasize to consumers that improved IAQ using UV-C has the dual benefit of providing healthier breathing for occupants while reducing air-handler coils’ susceptibility to mold and bacteria buildup,” said Jones. “As for cost, UV can be installed for an average of less than 15 cents per cfm — a mere fraction of the 10-25 percent potential energy and maintenance savings yielded by the efficiency-enhancing technology. Ultimately, UV-C has a proven record of improving IAQ, reducing maintenance, and boosting energy efficiency.”


Implementing a regular maintenance program is important in all buildings, especially ones that utilize cooling towers, which can foster the growth of legionella, the bacteria that cause Legionnaires’ disease. “There is heightened attention and emphasis on building owners and facility managers to minimize the risks of an outbreak, not only for their own mitigation of risks but also for the health and well-being of building inhabitants,” said Ray Field, director of liquid solutions, Goodway Technologies.

Regular maintenance should include cleaning cooling tower basins, which are naturally susceptible to legionella growth due to the stagnation and buildup of mud and dirt that can form a biofilm that allows dangerous bacteria form and flourish. “We offer a cooling tower vacuum, the CTV-1501, which is a clean-in-place solution that helps dislodge and vacuum up mud and silt for easy disposal and leaves cooling tower basins cleaner, safer, and operating more efficiently,” said Field.

Cooling tower fill can also be an area in which biofilms occur, so regular cleaning of lime scale, debris, and biological matter is a good idea. “Our cooling tower fill cleaner, the TFC-200, utilizes patented chemical solutions and pump technology to dissolve scale deposits, increase water flow, and slow dangerous biological buildup,” said Field. “There’s no need to remove fill because this is a clean-in-place solution that can be done at the tower location.”

The benefits of regular maintenance extend beyond reducing the risk of Legionnaires’ disease and other serious IAQ problems, it also prevents equipment breakdown, downtime, and increased energy costs. “Preventive maintenance can reduce the need for more complex repairs and extend the life of equipment,” said Field. “Contractors are at the forefront of cost savings for facilities. Through proactive maintenance programs, contractors can help improve IAQ and deliver considerable cost savings.”


Regardless of the building use and type, there are several common IAQ problems that can be found in most applications. These include volatile organic compounds (VOCs), which are off-gassed from construction materials and indoor furnishings, such as carpeting, tables, and other types of furnishings; human activity, which includes bioeffluents, such as CO2, which can cause cognitive impairment at higher levels; and indoor air contaminants that are released into the indoor air from many common cleaning compounds and other human activities, explained Nick Agopian, vice president of sales and marketing, RenewAire. “These IAQ problems can usually be solved by adequately ventilating the space.”

Ventilation has always been one of the most effective ways to enhance IAQ, and energy recovery ventilators (ERVs) are designed to generate the simplest form of source capture and air change with fresh outdoor air. “ERVs remove stale and contaminated indoor air and replace it with fresh and filtered outdoor air that’s tempered with the otherwise wasted energy of the heat and humidity from the exhaust airstream. This process results in a lower steady-state concentration of the gases and contaminants generated from the inside as well as less energy used by the HVAC system,” noted Agopian.

“Our ERVs are simple to apply, install, maintain, and operate,” he said. “They consist of a static core, so there are no moving parts, which maximizes reliability, and there’s very little maintenance other than vacuuming it once every six months to a year and changing the particulate filters. The mechanical rotating components used in our ERVs are also tremendously reliable and often last decades.”

Building owners who install ERVs may also likely see substantial returns on their investments, said Agopian. “The internal rate of return exceeds 45 percent, and the net present value of future cash flows on an investment of $6,000 is nearly $40,000 over 15 years. ERVs have no increased costs, and the cash flow and return on investment are always positive, no matter what metric is applied. The bottom line is that our ERVs offer substantial energy savings, a competitive price, a short payback period, reliability, enhanced IAQ, and better indoor comfort, but, most importantly, they improve the human condition.”


Fluctuating and low relative humidity (RH) levels can contribute to a number of problems in commercial applications, including increased employee illness and damaged equipment and building contents. “Other problems can include production line disruptions or failures, loss or degradation of materials, and inconsistent environmental conditions in labs and other critical applications,” said John Kimmes, senior technical support representative, DriSteem. “That is why it is helpful to understand the importance of humidity in creating good IAQ as well as knowing the types of humidification equipment and controls available.”

The benefits of humidification are heavily dependent on what is going on inside the building. For example, in health care environments, humidity levels are a regulatory issue, explained Kimmes. “In controlled settings, such as a laboratory or museum, it’s essential that the indoor environment conditions do not fluctuate, otherwise valuable equipment, materials, and artifacts can be compromised or damaged. In printing and graphics production environments, proper humidity levels can reduce quality problems, such as unwanted ink marks caused by static electricity.”

Contractors should be aware that humidification systems need to be carefully sized for buildings and their total load. Over time, as the building structure, activities, and requirements change, humidification strategies should also be reviewed and realigned, said Kimmes. “Contractors should address the topic of air quality regularly and ensure it is included in ongoing project planning. They should also use reliable, quality products, including DriSteem’s full range of commercial and industrial humidification equipment and controls.”

Publication date: 12/26/2016

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