Lucas Hamilton is Manager, Building Science Applications for CertainTeed Corporation
If you follow organizations and companies dedicated to sustainable solutions such U.S. Green Building Council, Leadership in Energy and Environmental Design (LEED) or even this Blog you have probably seen an increased discussion about VOCs or Volatile Organic Compounds. But I am not sure that people, in general, are aware of how pervasive VOC’s are in our lives.
By definition a Volatile Organic Compound is an organic material with a growing point less than 250° Fahrenheit. For most of us this means that these organic compounds tend to exist as gases. They are in many products that we buy and they also can occur naturally. They have a wide range of adverse health effects including eye and respiratory tract irritation, headaches, dizziness, visual disorders, and memory impairment in other words, they are not good for you! Organizations such as the Environmental Protection Agency (EPA), Occupational Safety and Health Administration (OSHA) and Health Canada have clearly spelled out the effects of long-term exposure to elevated concentrations of VOCs.
Most people recognize the presence of VOCs by their smell. They have a distinctively unnatural smell. I always tell people if it smells bad it is bad. We all have a genetic memory in our bodies that identify bad smells.
As I have mentioned in a previous blog about tightening the building envelop, VOCs are all around us. They are found in cleaning products we use, carpeting, paint, lacquers, printing products – there is an exhaustive list.
When VOCs are part of interior air you only have three methods of reducing them: capture them, kill them off, or ventilate them away. In terms of capture ordinary particle filters do not work. Filters made of activated charcoal are good at capture but these filters don’t work at the high air speeds which occur within our HVAC systems. Emerging technologies, such as AirRenew® which we’ve spoken of before, provide a new means of sequestration which HVAC filters do not. To “kill them off” requires ultraviolet light (UV). Formaldehyde, for example, has a 14 day half life in the presence of UV but we don’t have much UV inside our buildings. This leaves ventilation as a functional option. Providing fresh air ventilation rates in accordance with ASHRAE 62.1 for commercial buildings and 62.2 for residential buildings is a good place to start.
Trust your olfactory system – if it doesn’t smell right you may have a build-up of volatile organic compounds!