AIVC - Air Infiltration and Ventilation Centre

Search form

EBC

You are here

Home

carbon dioxide

Quantitative relationships between classroom CO2 concentration and learning in elementary schools

The data from published studies were used to build relationships between learning outcomes and air quality in classrooms. Psychological tests measuring cognitive abilities and skills, school tasks including mathematical and language-based tasks, ratings schemes and tests used to assess progress in learning including end-of-year grades and exam scores were considered to represent learning outcomes. Indoor air quality was characterized by concentrations of carbon dioxide (CO2). Short-term sick leave was included as well because it can influence learning.

A New Approach to Estimating Carbon Dioxide Generation Rates from Building Occupants

Indoor carbon dioxide (CO2) concentrations have been used in the fields of building ventilation and indoor air quality (IAQ) for decades. Specific applications include the estimation of ventilation rates, control of outdoor air ventilation rates based on indoor CO2 as an indicator of occupancy, and use of CO2 as an IAQ performance metric. All of these applications require values for the CO2 generation rates of the occupants of the space or building being considered. Human CO2 generation rates depend on their level of physical activity as well as their sex, age, and body size.

Capture efficiency of air curtain assisted residential range hoods

Air curtain assisted range hoods are very customary in large industrial kitchens. They allow to increase the capture efficiency of the range hood while lowering the net exhaust flow rate. For applications in residential settings, there is a lack of data on the performance of air curtain assisted range hoods, as well as a lack of information on the required settings and boundary conditions to come to the successful application of air curtain assisted range hoods.

Effects of Carbon Dioxide With and Without Bioeffluents on humans

Carbon dioxide (CO2) has traditionally been assumed innocuous at the typical levels indoors, and merely an indicator of metabolic emissions from humans (bioeffluents). Recent studies suggest that exposure to pure CO2 at concentrations of 2,500 to 4,000 ppm, the levels that occur periodically indoors, can have negative effects on mental performance in form of reduced ability for making decisions, typing and proofreading. Present study aimed to examine further these effects. Twenty-five human subjects were exposed to elevated CO2 with and without bioeffluents in a chamber.

Indoor Carbon Dioxide Concentrations in Ventilation and Indoor Air Quality Standards

Indoor carbon dioxide (CO2) concentrations have played a role in discussions of ventilation and indoor air quality (IAQ) since the 18th century. Those discussions have evolved over the years to focus on the impacts of CO2 concentrations on building occupants, how these concentrations relate to occupant perception of bioeffluents, the use of indoor CO2 concentrations to estimate ventilation rates, and CO2–based demand control ventilation. This paper reviews how indoor CO2 has been dealt with in ventilation and IAQ standards in the context of these issues.

Impact of the new rite 2013 (regulation on thermal installation) on indoor air quality

This paper presents a comparison of Indoor Air Quality in several buildings constructed prior to the implementation of the new Spanish regulation on thermal installations (RITE, 2007 modified on 2013) and some new ones that fully accomplish the requirements of this new regulation.

CO2 and volatile organic compounds as indicators of IAQ

The trend toward minimizing ventilation of houses in order to reduce energy consumption for heating and cooling leads to an increase in indoor air pollution. The deterioration of indoor air quality (IAQ) negatively affects human health, safety, productivity and comfort. In order to evaluate the scale of this influence IAQ assessment has to be performed. However, the IAQ itself is not well defined and a number of parameters are considered as its indicators. In this work we compared carbon dioxide and volatile organic compounds as indicators of indoor air quality.

Carbon Dioxide Concentrations and Humidity Levels Measured in Belgian Standard and Low Energy Dwellings with Common Ventilation Strategies

One of the most commonly used strategies to reduce the heating demand in low energy buildings is reducing the leakage level of the building envelope. Dedicated ventilation systems are then installed to compensate for the reduced air change rate in an energy efficient way. Most occupants, however, operate their ventilation system at very low flow rates. Together with the emission of bio-effluents, linked to the presence of the occupants, moisture production related to household activities is one of the most important sources of indoor air pollution in dwellings.

Air Change Rate Measurements using Tracer Gas Carbon Dioxide from Dry Ice

Air change rate is often used as an important characteristic of indoor environmental quality, which significantly impacts human health. However, easy, effective, real-time and low-cost air change rate measurements in naturally ventilated resident buildings are still a huge challenge. This paper presents a method based on the release of a stable rate of the tracer gas CO2 given off by solid CO2 (dry ice) in an insulated box.  In theory, the dry ice will sublime at a constant rate as long as there is sufficient dry ice in the box.

Pages