Serious Chemical Threat Sniffer on a Budget
Chemical warfare detection was never supposed to be a hobbyist project. Yet here we are: Air Quality Guardian by [debdoot], the self-proclaimed world’s first open source chemical threat detection system, packs lab-grade sensing into an ESP32-based build for less than $100. Compare that with $10,000+ black-box hardware and you see why this is worth trying at home.
It’s nothing like your air monitor from IKEA. Unlike those, or the usual indoor monitors, this device goes full counter-surveillance. It sniffs for organophosphates, carbamates, even stealth low-VOC agents designed to trick consumer sensors. It flags when incense or frying oil is used to mask something nastier. It does so by analysing raw gas sensor resistance – ohm-level data most devices throw away – combined with temporal spikes, humidity correlations, and a database of 35+ signatures.
This technology – once only available in expensive military labs – can be useful in many situations: journalists or whistleblowers can record signs of chemical harassment, safehouses can notice when their air changes in suspicious ways, and researchers can test strange environmental events. Of course, you must take care with calibration, and sometimes the system may give a false alarm. Still, just having such a detector visible already makes attacks less likely.
Featured Image by Arjun Lama on Unsplash