PM2.5

Highly energy efficient buildings such as ones built to the Passive House standard, require a very airtight building envelope and the installation of a mechanical ventilation with heat recovery (MVHR). MVHR systems incorporate ambient air filters, which reduce the introduction of particulate matter (PM) from outdoor sources into the dwelling. However, indoor PM sources, e.g. cooking, can also contribute substantially to occupants’ exposure and need to be accounted for when designing ventilation or deriving recommendations for filter classes. 

Over the past few years there have been advances in sensing of some pollutants, primarily particles, that might lead to ventilation controls based on direct sensing of pollutants – particularly those relating to health. In this study we evaluated low-cost (about $200 US) IAQ monitors that measured PM2.5 - the most important health-related pollutant in indoor air. Controlled laboratory tests were carried out with known sources of particles (cooking, cleaning, candles, cigarettes) and by comparing the IAQ monitors response to research-grade and reference measurement methods.

Product connectivity makes products and systems remotely controllable and possibly interoperable with other devices in the house. 
The most common way to achieve this interoperability is to connect these devices locally. On the other hand, products may also be cloud-connected, which allows an easier and seamless interoperability between devices. Hence, data are collected and stored in the cloud. As soon as the measured data is sent to the cloud, large set of data are available and can be anonymously retrieved and statistically analyzed. 

According to past researches, most people spend 80%-90% of their time indoors. The ventilation is very important to people’s health and the comfortable surroundings around us. From the viewpoint of energy saving, mechanical ventilation will consume a large amount of additional energy. So variety of ways measuring natural ventilation is worth considering. In fact, in real life, many people tend to have their windows shut rather than open, and the reasons are complex.

The objective of this study is to provide research results of the actual conditions concerning theconcentrations of PM10, PM2.5, PM1 and CO2 among particle and gaseous pollutants in a subwaycarriage. Mean concentrations of PM10, PM2.5 and PM1, and CO2 in a subway carriage wereinvestigated as 215.1101.4 ? m-3, 86.938.6 ? m-3, 27.011.4 ? m-3, and 1,588714 ppm,respectively. These mean concentrations in a subway carriage were higher when it ran on anunderground track than on a ground track.

In this study the question whether or not and to what extend ventilation and air cleaning can contribute to the reduction of exposure to environmental tobacco smoke in the hospitality industry is answered. First a literature review on ventilation and air cleaning technologies has been executed. Unfortunately, only a few papers reporting experimental data from the hospitability industry were available to answer the proposed question. Therefore a model describing the effect of different ventilation systems and building layouts has been set up.

A survey of the particle-size distribution of 17 polycyclic aromatic hydrocarbons (PAHs) in indoor and outdoor air was performed in 20 homes in several Japanese cities. Highest PAH concentrations were found in the fine-particle fraction (smaller than 2.5 μm in diameter). The pro· portion of indoor PAH concentrations in fine particles was found to be higher than that of outdoors.