This document describes the design and implementation of a Smart Environmental Air Pollution Monitoring System (SEAPMS) based on IoT. The SEAPMS uses sensors to detect concentrations of gases like carbon monoxide, carbon dioxide, methane, dust, smoke, temperature and humidity. The sensor data is sent to a Particle Photon microcontroller, which then sends the data to the UBIDOTS IoT platform and cloud for analysis and visualization. The system also includes a fire extinguishing component that will activate when smoke concentration exceeds a threshold limit.