air exchange rate

Ventilation plan for smoking room must deal with pollutants since they affect the air quality of adjacent rooms. Although ventilation plan typically maintains a negative room pressure to remedy this problem, the transport of indoor air pollutants between rooms is affected by moving objects, such as human movement and door opening. The purposes of this study were to evaluate the effects of moving objects on the rate of transport of indoor air pollutants and to propose a method of controlling contamination for smoking room.

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.

A pilot survey was undertaken from September 2009 to June 2011 in 310 schools and day-care centres distributed in all regions of France including overseas departments. This experimental survey was carried out as part of the preparation of the mandatory control of indoor air quality in public buildings. Three parameters were measured in 896 classrooms or child playrooms: benzene, formaldehyde and carbon dioxide (CO2). The last enables the determination of degree of air ‘stuffiness’ during children occupancy as well as the night-time air change rate.

Age of air is a technique for evaluating ventilation that has been actively used for over 20 years. Age of air quantifies the time it takes for an elemental volume of outdoor air to reach a particular location or zone within the indoor environment. Age of air is often also used to quantify the ventilation effectiveness with respect to indoor air quality. In a purely single zone situation this use of age of air is straightforward, but application of age of air techniques in the general multizone environment has not been fully developed.

Studies on buildings have shown that airtightness and insulation increased in family buildings and detached houses too, due to new thermal regulations. In the same time, studies concerning health and indoor air quality have shown that the need of fresh air will increase too.

In moderate climates, one promising feature to reduce the energy demand of office buildings for air conditioning without reducing comfort is passive cooling by night ventilation. An office building has been designed, realised and monitored for a long time period in the framework of the German research programme solar optimised buildings. The night cooling of the office building has been realised by natural ventilation.

Describes how a physical compartmental model (INTAIR) has been parameterised to estimate PM10 concentrations and has been used to assess the contribution of smoking to PM10 levels for typical homes in the UK. Concludes that smoking activity at home increases the daily mean concentrations in the living room by 1-1.5 microgrammes per m3 per cigarette smoked, and that this may contribute significantly to personal exposures to PM10.

The development of new highly sensitive detection techniques for particle bound polycyclic aromatic compounds (PP AH) on the nano-particles of traffic born soot open a new dimension for real time measuring techniques for air exchange rates in buildings in operation. The principles and first measurements are presented and demonstrate the principal applicability of this method.

The process of air exchange can be described through both planar and spatial network system. It depends on a few random variables (those related to climate) and also on controlled variables (i.e. those like arrangement, etc.). Consequently, the air exchange problems are solved only approximately. In order to avoid that, a neural model was applied as well as estimation in the so-called learning process with simultaneous weight correction. On the basis of comparison with experimental data it can be claimed that solutions presented in the paper demonstrate high result congruence.