Pollutant emission rates from indoor combustion appliances and sidestream cigarette smoke

Abstract

Particulate and gaseous emissions from indoor combustion appliances and smoking can elevate the indoor concentrations of various pollutants.Indoor pollutant concentrations resulting from operating one of several combustion appliances, or from sidestream tobacco smoke, were measured in a 27-m 3 environmental chamber under varying ventilation rates. 7he combustion appliances investigated were gas-fired cooking stoves, unvented kerosene-fired space heaters, and unvented natural gas-fired space heaters. Results showed elevated levels of carbon dioxide, carbon monoxide, nitric oxide, nitrogen dioxide, formaldehyde, and suspended particles from one or more of the pollutant sources investigated. Our findings suggest that, of the sources examined in this study, nitrogen dioxide from combustion appliances and particles from sidestream cigarette smoke are the most serious contaminants of indoor air, if we use existing standards and guidelines as the criteria. An emission rate model was used to quantify the strengths of the pollutant sources, which are reported in terms of the mass of pollutant emitted per energy unit of fuel consumed (in the case of gas and kerosene appliances) and per mass of tobacco combusted (in the case of smoking). IUTRODUCTIOUIndoor combustion appliances and tobacco smoking are primary sources of air pollution in many residences. Gas-fired stoves and unvented space heaters (both kerosene-and natural gas-fired types) emit such potentially harmful pollutants as carbon monoxide (CO), carbon dioxide (C0 2 ), nitric oxide (lTO), nitrogen dioxide (no 2 ), sulfur dioxide (S0 2 ), formaldehyde (IlCIIO), and respirable particula_tes; sidestream tobacco smoke contains CO, co 2 , no, no 2, respirable particulates and a wide range of organic compounds. The degree of indoor air pollution and, therefore, the degree of health risk to occupants from these sources depends on the type and amount of pollutants entering the occupied space, and the rate of removal by processes such as infiltration, mechanical ventilation, and chemical reactions.Calculating emission rates of these combustion-generated pollutants is an essential step in assessing the degree to which these pollutant sources affect indoor air quality. In this paper, we report the pollutant emission rates derived from our studies of a gas-fired stove, gasfired unvented space heater, kerosene-fired unvented space heater, and sidestream cigarette smoke. EXPERIUEUTALExperiments were carried out in an environmental chamber under controlled ventilation conditions; our Hobile Atmospheric Research Laboratory (ltARL) was used to measure gas-phase pollutant concentrations.-1-Both the 27-m 3 environmental chamber and the l~ are depicted schematically in Fig. 1. The chamber can be operated under conditions of natural infiltration, typically providing· less than half an air change per hour (ach), or under mechanical ventilation, providing higher air exchange rates. Small, variable-speed fans centered on each chamber wall provide mixing of the air to insure unifo...

A Critical Review

“…14 In work performed at LBL tests on a gas-fired space heater showed emissions of CO to be 655 /ig/Kcal. 27 In this same work, the LBL workers showed that sidestream cigarette smoke .produced 130 jug CO/mg of tobacco burned. This value is about half that reported in the NAS report.…”

Residential Air Pollution from Kerosene Heaters

“…2 /1000 Btu/h heater capacity, a recommendation of some manufacturers, should be provided to minimize the accumulation of contaminants. Purchasing an oversized heater or operating a heater in a smaller room than that for which it was intended will result in high, and possibly unsafe concentrations of air pollutants.…”

Formaldehyde Concentrations Inside Conventional Housing

“…First, residential combustion sources have been shown to be relatively weak sources of formaldehyde in emissions tests, 33 and no significant contribution of these sources to indoor formaldehyde levels has been ascertained in several large field studies. (Table III) showed no correlation (R = -0.01) with weekly averages of simultaneous measurements of indoor NO2.…”