indoor air quality

Ventilation air may be provided in buildings by means of natural or mechanical strategies. When a HVAC system is installed, thermal comfort and indoor air quality (IAQ) may be controlled with higher precision. However, especially between the 70s and the 90s, mechanical ventilation systems have been installed on formerly naturally ventilated buildings without providing any control for natural ventilation.

In 2011, the Danish Energy Agency initiated a study into ventilation solutions for the retrofit of schools to identify the most promising technologies. The reason was an increasing awareness that the ability of school children to absorb, adapt and use knowledge was affected negatively by inadequate ventilation rates. This paper presents an output of this study. A method for evaluation of the ventilation systems is proposed. The method consists of three categories with a clear separation to create a scoring board that facilitates transparent and unbiased evaluation.

Ventilation’s historical goal has been to ensure sufficient air change rates in buildings from a hygienic point of view. Regarding its potential impact on energy consumption, ventilation is being reconsidered today. An important challenge for low energy buildings lies in the need to master airflows through the building envelope. Data collected from controls in 1287 recent dwellings shows us that 68 % of the dwellings don't respect the French airing regulation.

The aim of this study is to analyse the behaviour of natural ventilation techniques in low-rise commercial buildings in terms of Indoor Air Quality (IAQ).

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.

It is estimated that people spend 60-90% of their life in indoor environments. Therefore, it is obvious that indoor air quality (IAQ) and thermal comfort are of highly importance for the health and wellbeing of the population. Consequently, buildings should be designed to ensure proper indoor conditions. Furthermore, the need to mitigate climate change and to reduce energy import dependency, provides additional challenges for the design and operation of buildings and requires a dramatic reduction in their energy consumption and emissions.

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.

The long term exposure to fine particulate matter with a diameter of ≤2.5 μm (PM2.5) is linked to numerous health problems, including chronic respiratory and cardiovascular diseases, and cancer. In dwellings, a primary emission source of PM2.5 is cooking, an activity conducted several times per day in most households. People spend over 90% of their time indoors and more time in their homes than any other type of building. Therefore, they are at risk of exposure to elevated levels of PM2.5 emitted by cooking if these particles are not removed at source.

At typical indoor CO2 levels there is no scientific evidence that CO2 is harmful to comfort and health of healthy persons, though there is a potential for negative effects on some aspects of performance. Research also indicates that insufficient bedroom ventilation may negatively affect the quality of sleep.