Design & Development of Low Cost Decibel Meter

Noise pollution has emerged as a significant environmental and public health issue due to rapid urbanization, increasing traffic density, and widespread use of electronic devices. Prolonged exposure to high noise levels can lead to adverse health effects, including hearing impairment, stress, reduced concentration, and sleep disorders. Although monitoring noise is essential for awareness and prevention, the high cost of commercial sound level meters limits their accessibility, particularly in educational settings. This study presents the design and development of a low cost digital decibel meter using an Arduino microcontroller to promote noise pollution awareness and support environmental education. The system comprises an Arduino UNO, a microphone sensor module (KY-038 or MAX4466), a 16×2 LCD display, and basic electronic components. Ambient sound is detected by the microphone sensor and converted into electrical signals, which are processed through analog-to-digital conversion to estimate sound intensity levels in decibels. The measured noise levels are displayed in real time on the LCD interface. The device was tested in multiple locations, including classrooms, playgrounds, and roadside areas, and calibrated using smartphone-based decibel meter applications to enhance measurement consistency. The results showed noticeable variations in noise levels across different locations, demonstrating the system’s effectiveness in identifying high-noise zones. While the measurements are approximate, they are sufficiently reliable for educational use and awareness activities. The developed system provides an affordable and practical tool for introducing students to concepts in acoustics, electronics, and embedded systems, while encouraging active participation in environmental monitoring. This work highlights the potential of low-cost technological solutions in addressing environmental challenges and offers scope for future enhancements such as data logging, wireless connectivity, and integration with smart monitoring platforms.