Ventilation Influences Indoor Air Contaminants
At the May 2014 meeting of Westcon construction consultants, Bud Offermann presented “Ventilation: What a long, strange trip it’s been.”
Ventilation has been and remains the dominant removal mechanism for indoor air contaminants, including moisture and odors. Despite its importance, ventilation remains somewhat of an invisible and often ignored attribute when decisions are made in the design and operation of buildings.
Ventilation is more than just delivering outdoor air to a space. Ventilation influences the concentration of indoor air contaminants through creation of building air pressures and through air filtration.
Ventilation systems have 3 basic functions they can provide regarding indoor air quality.
- Provide oxygen.
- Provide thermal comfort.
- Remove air contaminants.
Field Studies Have Changed California Homebuilding
Ventilation in residences has, until recently, been provided simply with openable windows. In 2009, Indoor Environmental Engineering completed the first large field study of ventilation and indoor air quality in 108 new California homes. Out of this and other studies emerged two major changes to how we build homes in California:
- The California Energy Commission adopted the 2008 Building Energy Efficiency Standards, which requires all single-family detached residential buildings to have a mechanical outdoor air ventilation system. This was the result of the finding that many people never or rarely open windows for ventilation as a result of concerns for security/safety, noise, dust, and odor concerns.
- The California Air Resources Board adopted in 2007 an airborne toxics control measure (ATCM) to reduce formaldehyde emissions from composite wood products including hardwood plywood, particleboard, medium density fiberboard, and also furniture and other finished products made with these wood products. This was the result of the finding that formaldehyde posed a significant health risk and that ventilation could not by itself control the indoor concentrations, but reduction of the emissions are needed to reduce indoor concentrations to acceptable levels.
About our speaker:
Mr. Offermann has over 35 years of experience as an IAQ researcher, sick building investigator, mitigation planner, healthy building design consultant and expert witness.