New Study Investigates Impact of Vent-Free Gas Heating Appliances in “Tight” Home

ARLINGTON — A new study on nitrogen dioxide (NO2) emissions from vent-free gas fireplaces, logs, inserts, space heaters, and stoves found that the use of those appliances in “tight” homes does not result in NO2 concentrations that exceed guidelines for indoor air quality. “Tight” homes are those that are designed to be as air-tight as possible, usually with mechanically controlled ventilation. Today, many new homes are designed in this manner. The study was commissioned by the Vent-Free Gas Products Alliance Product Section of the Air-Conditioning, Heating, and Refrigeration Institute (AHRI), and included 100,000 simulations. The details of the study are available in PDF.