The fume sniffer that keeps yelling at me

A particle sensor + RP2040 on the bench arm. It works. It also thinks toast is a hazardous material.

Status: in progress. The hardware is done — an SPS30 particle sensor talking to an RP2040, mounted on a swing arm above the bench. The firmware is technically done. The calibration is, charitably, ambitious.

The premise

Solder fumes are bad. The fan helps. But the fan is in the wrong place half the time because I’ve moved the work and forgotten to move the extraction. The fume sniffer is supposed to nag me until I fix it.

The problem

It nags me when I make toast in the next room. It nags me when a hot air gun fires up two metres away. It nags me when the cat walks past the sensor, which I cannot explain. The threshold logic needs work.