Submitted by Maria.Kapsalaki on Wed, 09/18/2013 - 17:12
Existing thermal comfort standards and methods cover mainly thermal comfort conditions under steady state conditions. Most of the thermal comfort studies have been carried out in laboratories and are based on evaluations of the heat transfer between the human beings and their environment and of the required physiological conditions for thermal comfort.
The present Ventilation Information Paper aims to present the basic knowledge on the use of earth to air heat exchangers. The increased need for air conditioning has made alternative passive and hybrid cooling techniques very attractive.
An intentional or accidental large-scale airborne toxic release (e.g. terrorist attacks or industrial accidents) can cause severe harm to nearby communities. Under these circumstances, taking shelter in buildings can be an effective emergency response strategy. Some examples where shelter-in-place was successful at preventing injuries and casualties have been documented. As public education and preparedness are vital to ensure the success of an emergency response, many agencies have prepared documents advising the public on what to do during and after sheltering.
In the past and still often today, building regulations and standards don't reflect the state-of-the art with respect to the performance assessment of buildings in terms of energy use and indoor climate. Because of the field of most of these regulations (transmission losses, energy demand for heating,...) and the typical used components, the assessment procedures were rather simple and not really a reflection of the physical behaviour (e.g. dynamic behaviour of buildings).
If the building envelope is not airtight enough, significant amounts of energy may be lost due to exfiltrating air, or damage to structural elements may occur due to condensation. Air leakage can be avoided by appropriate design and careful construction. Test methods to check the quality of airtightness and to locate the individual leakages are available and are increasingly used.
Submitted by Maria.Kapsalaki on Wed, 09/18/2013 - 17:07
VIP Indoor Air Pollutants, Part 1 defined major types of indoor air pollutants, their measurement, and concentrations guidelines. This second part of the VIP addresses the sources of pollutants and effective measures to control them or to mitigate their impacts on occupants and building contents. The most effective means to control indoor air pollution is through reduction or elimination of pollution sources. Indoor pollutants originate both within the building and from outside. The first step in controlling the sources of indoor air pollution is to identify them.
A heat recovery unit transfers heat (some units also moisture) from the exhaust air stream over to the supply air stream, thus reducing the heat loss due to ventilation, and reducing the need to condition the cold supply air. Conversely, in hot and humid outdoor conditions, a heat recovery unit can keep heat (some units also moisture) outside, thus reducing air conditioning costs.
Addressing successful solutions to counterbalance the energy and environmental effects of air conditioning is a strong requirement for the future. Possible solutions involve the use of passive cooling techniques and in particular of heat and solar protection techniques, heat amortisation and heat dissipation techniques. Recent research has shown that night ventilation techniques may contribute highly to improve thermal comfort in free floating and decrease the cooling energy consumption of air conditioned buildings.
Natural ventilation is one of the most effective passive cooling techniques. Because of the serious reduction of the wind speed in the urban environment and the corresponding reduction of the air flow rate, for both single and cross configurations, the cooling load on the buildings inside the canyons is much higher than the one of buildings where wind is not obstructed. Thus, it is very important to consider, other techniques than windows to enhance air flow in urban buildings.
Submitted by Maria.Kapsalaki on Wed, 09/18/2013 - 17:02
Pollutants found in indoor air are often several times higher than outdoors. Indoor air pollutants cause effects ranging from odor, annoyance, and irritation to illness, cancer, and even death. Since people spend the majority of their time indoors, it is important to recognize and control indoor air pollution. Some indoor air pollutants also adversely affect materials in the building and the building structure itself. The majority of indoor pollution comes from the building itself, its contents, or its occupants and their activities.