Due to industrial development, air pollution in China has become more and more serious in recent years. Air pollution has resulted in huge human and financial costs in China. The World Health Organization (WHO) has been tracking air quality since 2013 to assess its impact on heart disease, stroke, lung cancer and other respiratory diseases. In 2015, more than 1.1 million deaths in China and India were linked to air pollution, accounting for half of the world's total air pollution deaths that year.


Even indoors, air pollution is still serious but people tend to ignore it. Detecting indoor PM2.5 indicators in real time thus helps people to take some necessary measures such as wearing masks as well as turning on air purifiers.


We have designed a small PCB using STM32 as the main controller, the PCB is connected to a haze detection sensor for real time detection of PM2.5 values in the environment. A piece of ESP8266 is also embedded for connecting to the internet and transmitting the data to the server.

In addition, we modified an existing penlight with a small screen to display the real-time PM2.5 value, which is both convenient and practical.


Indoor Haze Detector, PM2.5, STM32, ESP8266


Photos and video taken at the 2017 Zhengzhou University IoT Innovation Laboratory.


Figure 1. First generation prototype made from scrap paper.

Figure 2. Second-generation prototype made from a metal box.


Video 1. Third-generation prototype made on the basis of a pen holder.

Video 2. Third-generation prototype made on the basis of a pen holder.