PM2.5

Achieving energy-efficient dwellings has become a vital part of the global climate action plan to reduce energy usage and carbon emissions. Deep energy retrofits (DER) can help reduce residential energy use significantly. However, evidence on how DER impacts on indoor air quality (IAQ), and consequently, occupant health, is scarce. More in-depth analysis of IAQ data before and after energy retrofits is essential to understand the indoor environmental challenges of adopting energy efficiency measures.

Indoor air quality in residential buildings has been attracting more attention from the public. Many portable air cleaner products have been developed and are available in the market. Manufactures generally claim that those portable air cleaners can efficiently remove PM2.5 and/or TVOC and can also remove virus from the indoor air. However, no standards are available to have the claimed efficiency comparable and thus unclear effect in applications at homes.

Outdoor PM2.5 has a continuous and significant effect on the indoor environment, and lobby floors, in particular, can be exposed to high concentrations due to entrance doors and greater airflow rates than other floors. In this study, the PM2.5 indoor-to-outdoor (I/O) ratio for lobby floors was evaluated according to the operation type and configuration of entrance doors. Airflow analysis was conducted for an office building with multi-zone network simulation, and the I/O ratio was evaluated for different entrance strategies according to the occupant traffic schedule.

In the current era, sensors in buildings have become an essential requirement for wide applications such as monitoring indoor air quality (IAQ), thermal and environmental conditions, controlling building heating, ventilation, and air-conditioning systems (HVAC). To accurately control the IAQ for all areas in the indoor space, it is necessary to obtain considerable data from different locations in the space for more precision.

Indoor air quality (IAQ) control in educative centres, where students spend most of their time, is essential. The presence of high levels of contaminants can impact the academic performance of the students and, ultimately, their health. A study has been carried out to assess the IAQ of higher education classrooms with natural ventilation in order to quantify the exposure of the occupants to certain contaminants during the cold season. CO2, PM10, PM2.5, PM1.0, and volatile organic compounds (VOC) have been measured.

In building energy renovation, the notion of payback time of the investments is often presented as the only goal. However, the potential benefits in terms of health are also valuable despite being not consciously perceived by the occupant and may need to be monitored to be assessed. Laboratory-grade devices or protocols are generally burdensome and expensive, and the growing popularity of low-cost devices may contribute to the perception of health benefits at a larger scale.

The ALLO project aims to be innovative in the way it approaches information and its dissemination to residents who are concerned about air quality in their home or are not familiar with the subject. In this paper, we are focusing on one important pollutant, i.e. PM2.5, on more particularly on low-cost sensors that provides PM2.5 data in rooms at short timesteps (usually 5 min.).

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.