International Journal of Computer Applications (0975 – 8887) Volume 159 – No 6, February 2017 33 Automated Indoor Air Quality Monitor and Control D. Mahanth Mukesh (Bachelor of Technology) Department of Electronics and Communication Engineering GITAM University, Visakhapatnam Andhra Pradesh, India Sai Karishma Akula (Bachelor of Technology) Department of Computer Science and Engineering GITAM University, Visakhapatnam Andhra Pradesh, India ABSTRACT This paper presents a system of Automated Indoor Air quality Monitor which can be controlled and monitored using a mobile phone basing the concept of Internet of Things. The system monitors the indoor environment periodically and can be controlled using a Smart Phone. The system here is on internet of things platform which gives remote access through a mobile phone. The proposed system monitors the CO and CO 2 levels in the room and notifies the user if the tolerable limit exceeds. The user can turn on the vent fan from the smart phone, when the tolerable limit exceeds. This system was implemented using raspberry pi, which uses a database to store the monitored values and a web server which can be accessed through the smart phone. Keywords Internet of things, Raspberry pi, NGINX, SQLite, Python, Relay, COZIR, MQ-7, Android Studio 1. INTRODUCTION Carbon monoxide (CO) and Carbon dioxide (CO 2 ) are odourless and colorless gases which show some adverse effects on humans if they exceed the tolerable level. These days CO and CO 2 gases are higher indoors due to the increased human activities. CO 2 is added to the indoor environments due to respiration and other activities. CO is added to the indoor environment due to unvented kerosene and gas space heater, leaking chimneys and furnaces, back- drafting from furnaces, gas water heaters, wood stoves and fireplaces, gas stoves, generators and other gasoline powered equipment, automobile exhaust from attached garages, tobacco smoke, etc. [1]. Higher CO 2 levels affect the humans directly. A new study from the Harvard School of Public Health finds that carbon dioxide (CO 2 ) has a direct and negative impact on human cognition and decision-making. The Harvard study confirms the findings of a little-publicized 2012 Lawrence Berkeley National Laboratory (LBNL) study, “Is CO 2 an Indoor Pollutant? Direct Effects of Low-to- Moderate CO 2 Concentrations on Human Decision-Making Performance.” That study found “statistically significant and meaningful reductions in decision-making performance” in test subjects as CO 2 levels rose from a baseline of 600 parts per million (ppm) to 1000 ppm and 2500 ppm [2]. On the other hand Carbon monoxide (CO) affects the human health directly. At low concentrations health Effects Associated with Carbon Monoxide are fatigues in healthy people, chest pain in people with heart disease. At moderate concentration the effects are angina, impaired vision, and reduced brain function. At high concentrations the effects are impaired vision and coordination, headaches, dizziness, confusion, nausea, flu-like symptoms that clear up after leaving home, fatal at very high concentrations. Indoor air quality monitoring is an essential thing which ensures that the indoor environment is safe for living. Indoor air quality monitoring system monitors the levels of the particular gases like CO 2 , CO, N, etc. This process of monitoring the air quality may be done using various methods. By monitoring the indoor environment, the levels of the respected gases which are harmful can be known. Even though these gasses cannot be avoided completely, they can be reduced to a tolerable and safe level for humans. This can be done by installing the Ventilation Fans and turning them ON whenever these CO and CO 2 cross the safe levels [3]. In this paper the system proposed monitors the indoor air quality and also controls it. Here the CO and CO 2 sensors are used to monitor their levels and ensure that they are in the base level. There are some related works on this topic [4][5][6][7][8], but this paper proposes the automation of the air quality monitor system through a Smart Phone using the Internet of things platform. With this system the indoor environment can be monitored and controlled remotely. 2. SYSTEM ARCHITECTURE The system architecture of the proposed system for monitoring the indoor air quality is presented in Fig 1. The architecture is based on the Internet of things platform where the proposed system is connected to the internet [9]. This system enables the user to remotely access the monitored data and control the ventilation fan. Input Port: The General Purpose Input Output Ports receive the data from the sensors. These input ports act as an interface between the sensors and the raspberry pi. The data is now stored in the database installed in the raspberry pi. This data is processed and displayed to the user. Web Server: The web server is an application which serves the web pages over HTTP. A web server is created on the raspberry pi which hosts the data base, enabling the user to access the data base remotely and communicate to the requests from the user while giving response to the requests. Database: The data received from the sensors are stored in this database. The database is created on the raspberry pi web server. The database consists of data like time, level of CO and CO 2 , date. The data is received from the sensor in equal time frames. Smart Phone: The smart phone consists of an android app which will be connected to the web server hosted by the raspberry pi. Whenever the threshold of the tolerable level is crossed, the app notifies the user with an alert that the air quality is low. Then the user gets two options: Turn ON and Turn OFF. When the ON button is pressed the request is sent to raspberry pi and it responds to the request by turning the relay circuit ON. When the relay is ON, the Fan Turns ON and the CO, Co 2 levels come down slowly. When the indoor