Heating, ventilating, and air conditioning (HVAC) systems have had ozone applied to them on a large scale, there are some major reasons behind this, such as:
-The public has become growingly aware that indoor air quality (IAQ) can be can be improved
-Heightened intolerance towards smoking along with the increased knowledge that common chemicals can negatively impact IAQ
-Technological advancements within the ozone industry (particularly in ozone generators/monitors) make system controls more realistic
-Payback economics: savings in energy along with other factors
The main industrial sectors to heavily invest in ozone air treatment are gaming institutions like casinos, bingo halls, and card rooms, as well as applications within the hospitality industry (restaurants, showrooms, bowling alleys). These areas have seen high returns investing in air quality, in large part due to the common chemicals in these areas that would lower overall air quality (ex: cigarettes being allowed in most gaming buildings). Many smaller projects have also been applicated to places like taverns, designated smoking areas and advanced technology facilities where complete-building air treatment is not deemed necessary.
Most voiced objections towards ozone are in reference to its overall safety. When using ozone in public areas, the concentrations must be kept below the harmful levels. Self-controlling systems, that combine advanced ozone generation with ozone monitoring systems make this increasingly possible. However, among cognizant agencies, we do see discernment as to what should be deemed the safe levels and suitable ozone concentration guidelines. For areas where people gather together, the US FDA has stated a limit of .05 ppm. HVAC systems are programmed with automatic controls to typically stay under concentrations of .03-.05 ppm. However, these concentrations are lower than what we see occur naturally in outdoor settings, in most regions. “For ozone injected into HVAC systems it is absolutely necessary to include ozone sensors to automatically control the ozone concentration in areas where the public congregate.”
2 Major Applications
-Casinos: Gaming facilities are continually growing worldwide, and a majority of resorts are now including them. Smoking is typically found in high quantities in most casinos, and it is a major irritant for customers as well as employees. Ozone is incredibly effective in getting rid of the unpleasant smell caused by smoking, due to the variety of VOC’s that can be found in the smoke.
-Dubai International Airport: Odds are this is the largest ozonated HVAC system in the world, with the air treatment being applicated to all of the buildings. The airport has over 300 ozone sensor/controllers along with VOC sensor/controllers. There are many ozone generators spread throughout the HVAC ductwork, treating virtually all of the interior spaces. Preliminary findings from the Dubai International Airport were passengers and employees noted a pleasant air smell, as well as improved air quality. The airport also cut costs by spending less on maintenance, mainly because they no longer had to replace carbon filters.
Sources: Rip Rice, from the IOA https://www.ioa-pag.org/