Residential Formaldehyde Control by Mechanical Ventilation

Abstract

Studies of forced or mechanical ventilation applied for the control of residential formaldehyde levels were conducted in a urea-formaldehyde foam insulated (UFFI) house and in a mobile home. Air exchange rates were increased from base values (circa 0.2 ACH) to values in the range of 0.45–1.49 ACH by means of centrally installed heat-exchange ventilation systems. All studies were conducted under controlled temperature and humidity conditions. Formaldehyde levels were determined by the NIOSH chromatropic acid method.

Ventilation rates in the UFFI house in the range of 0.48–1.49 ACH were observed to be associated with percentage formaldehyde decreases in the range of 55–79 percent. In the mobile home, ventilation rates in the range of 0.45–1.33 ACH were observed to be associated with percentage formaldehyde decreases in the range of 57–67 percent. Over the range of ventilation rates evaluated, forced ventilation appeared to be more effective in the UFFI house than in the mobile home. Though increases in ventilation rates were observed to be associated with reductions in formaldehyde levels, this relationship was observed not to be linear. Because of the coupling effect between formaldehyde levels and source emission rates, forced ventilation for formaldehyde control is limited in its effectiveness and application as a residential control alternative. It is a viable mitigation measure when other measures are either too expensive or physically impractical.