[6] IIUM Research Ethics Committee Approval Letter (Ref: IIUM/504/14/8/1), 2020. Node assembly instructions and BOM (available from corresponding author). Appendix B: Sample SQL schema and Node.js subscriber code (GitHub link placeholder). Appendix C: Calibration curves for MQ-135 at IIUM’s average altitude (120 m ASL). This paper is a representative case study. Actual implementation details may vary; interested readers should contact IIUM’s Mechatronics Engineering Department for the latest documentation.
[5] R. A. Rahman and Z. S. Salleh, “Wireless Sensor Network for Fire Detection in University Buildings,” Journal of Engineering and Technology , vol. 8, no. 2, pp. 45–53, 2021. i-monitor iium
| Component | Model | Parameter Measured | Range / Accuracy | |-----------|-------|--------------------|------------------| | Microcontroller | ESP8266 (NodeMCU) / ESP32 | Processing & WiFi | – | | CO₂ & Air Quality | MQ-135 | CO₂, NH₃, benzene | 10–1000 ppm (CO₂) | | Temperature & Humidity | DHT22 | Temp, RH | ±0.5°C, ±2% RH | | Smoke & Combustible Gas | MQ-2 | LPG, smoke, H₂ | 300–10000 ppm | | Flame (UV/IR) | KY-026 | Fire (presence) | Digital 0/1 | | PIR Motion | HC-SR501 | Occupancy | 3–7 m range | | Light | LDR (5528) | Ambient light | 0–1023 (ADC) | [6] IIUM Research Ethics Committee Approval Letter (Ref: