Lastly improvement in buildings insulation united with molds and yeasts proliferation, and with the wide adoption of air conditioning had reduced air change rate inside buildings creating air stagnation and reducing breathable oxygen, leading to an air-quality impoverishment due to the presence of pollutants and toxic gases inside the rooms. In addition, molds and yeasts proliferation increases CO2 concentrations reducing breathable oxygen with several consequences on the health. The pollution issue is present also in the outside environment where the concentration of NOx to SO2 and micro particulate matter can exceed the limits. Basing on the WHO air quality guidelines, the concentration of several outdoor and indoor pollutants should be controlled. Prosecuting the activities started during the bilateral project "PRACTICE" (Planning Renewal Ageing Cities Towards Innovative Cellular Environments) and "SoURCE" (Sustainable Urban Cells), where was developed an age-friendly integrated air quality sensor called HOPES (Home Embedded Pollution System, elected as "project of the day" by Sapienza) a new prototype of wearable gas sensor called MEPS (Mobile Embedded Pollution System) is presented, a smaller version of HOPES. The system is a wearable thought to analyze the personal breathed pollutants. The system proposes an innovative approach, focused on people more than on the external environment; before protecting the environment, it is important to protect people from environmental pollution. MEPS project will help in monitoring real time pollutants in air helping people to reduce their exposure to hazardous gases and collecting position data helpful to the authority for managing purposes, green district and emergencies identification. It can be considered a mitigation measures that will help to keep breathed pollutants concentration averagely under the recommended values.
The wearable system (MEPS) will track people exposition to pollutants throughout the entire day. The system can change its color to easily communicate the air quality, while on the smartphone it is possible to control the daily exposition. The collected data will be sent to a web platform showing the overall air quality index and the user¿s position integrated with some easy to understand information like temperature and humidity trends as well as the concentrations of different gas families detected. Moreover, MEPS can be used to monitor the pollution in the surroundings, map critical zones and to help the authorities to manage outdoor pollution, set green zones or quickly discover gas leakage hazards.
Today there are no sensors able to solve all this issues at the same time. The main competitor devices are:
1. TZOA - http://www.tzoa.com/#homepage
It is an indoor air monitoring and cleaning system. Its ceramic catalyst (Ti oxides) is used to reduce the concentration of many pollutants, however the system it limited to indoor applications.
2. AIRCASTING - http://aircasting.org/
AirCasting is an open-source, end-to-end solution for collecting, displaying, and sharing health and environmental data using your smartphone. The platform consists in array of sensors that monitor noise, CO, NOx, temperature, humidity and (by another sensor) hearth and respiration rate. The main lack of the system is regarding the substances considered that are very few compared with MEPS. Moreover, its ecosystem is fragmentary, and it was developed to be assembled by technical people.
3. ATMOTUBE - http://atmotube.com/
The system analyses VOCs and CO, it completely lacks the GIS approach proposed with MEPS.
4. CLARITY - https://clarity.io/
A small PM2.5 sensor developed in China, where pollution level is very high. It is not a standalone device and is limited to PM2.5.
5. AERIO - http://www.tuvie.com/aerio-air-quality-sensor-by-nikolas-ethore/
It is only a concept.
During this project, the HOPES system will be miniaturized and simplified up to a wearable scale creating MEPS. Additionally, data can be associated with positional information from the GPS antenna of the connected smartphone and send to a GIS platform, creating pollution maps. The maps will permit citizens to avoid the more polluted areas or to learn about the pollution levels in their route. Finally, the data collected will be anonymous for security reasons. Thanks to the wide range of detectable substances, elements, MEPS can be considered as a step forward in air quality monitoring.