carbon dioxide

Operation of an unvented combustion appliance indoors can elevate pollutant concentrations. Under laboratory conditions, oxygen consumption rates and pollutant emission rates of CO, CO2, NO, NO2, HCHO and submicron suspended particles emitted

Air-to-air heat exchangers were evaluated as a method of maintaining indoor contaminant concentration levels below acceptable levels. A mathematical simulation of air infiltration and indoor contaminant generation was used todetermine the distribution of contaminant concentrations at various average intervals including hourly and yearly. Both spot generation such as from unvented combustion, and diffuse sources, such as from materials, were considered for four contaminants, nitrogen dioxide, carbon monoxide, carbon dioxide and formaldehyde.

A pilot test series has been performed to study the possibility of using carbon dioxide produced by the burners of a test furnace as a tracer gas to measure the fire gas leakage of door assemblies. The experiments show that a test method based on tracer gas techniques can be developed avoiding thedrawbacks of the proposed ISO test method DP 5925 Part 3 based on the use of an enclosure. The investigated method works well for leakage measurements in ambient and medium temperature ranges. A special test door suitable for theoretical estimation of leakage rates was used in the test.

The heating of air infiltrating through cracks around doors and windows forms an important part of the heat balance of buildings. The complexity of the problem makes it difficult to calculate. Describes the development of an insitu method for measuring the infiltration of buildings.

Pollutants in a substantial number of buildings have now been investigated by public and private agencies. The archive of data on indoor pollutant levels observed in office buildings under conditions of normal operation and occupancy are reviewed using a computer based Building Performance Database. Representative values of 153 pollutants as well as detailed frequency distributions of commonly measured pollutants and of temperature and humidity are presented.

For controlling and for setting ventilation standards to maintain acceptable indoor air quality, it would appear to be of greatest importance to determine the strength of relationships between contaminant concentrations on one hand and different rates of ventilation and how these rates are expressed on the other.

Tests were conducted in Ottawa during the winter of 1982/83 to investigate the effects of a gas cooking stove in the kitchen of an energy-efficient two-storey test house. Products of combustion: NO, NO2, CO and CO2, were measured in the kitchen, living room and bedroom in order to relate theinfluence of air infiltration and kitchen hood exhaust operation to the levels of air contaminants. Tests were also conducted, using the enclosed kitchen as a test chamber, to establish the values of emission rate for CO, NO and NO2and of reactivity for NO and NO2.

Measures of a number of ventilation parameters and of a number of pollutants from 21 locations furnished data for evaluating interrelations among commonly used descriptors of ventilation as well as their relation to frequently measured indoor gaseous and particulate pollutants.

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 or several combustion appliances, or from sidestream tobacco smoke, were measured in a 27m3 environmental chamber under varying vent ilation rates. The combustion appliances investigated were gas-fired cooking stoves, unvemed kerosene--fi red space heaters, and unvented natural gas-fired space heaters. 

Natural ventilation rates in bedrooms at night have been measured in retrofitted apartments. The measurements indicate clearly that air quality in bedrooms may be unacceptable in dwellings with an energy-efficient minimal ventilation rate. The air supply rates may be as low as 1 l/s/person in themedian case of bedroom size, ventilation rate and two occupants. The carbon dioxide concentration will reach a level of 4000-4500 ppm in the morning depending on the length of sleeping time in a closed room.