The sys admin's daily grind – Airsensor
Exactly How Smelly?

If the air in a room smells stale, somebody will get up and open the window to let in some fresh air. Charly, however, wanted to measure its exact staleness, so he set off to find out armed with USB hardware and Linux.
Stale air results from the accumulation of various gases in an enclosed room. Carbon dioxide is the classic case – just imagine 16 people in a small, windowless conference room. Add to this, a mixture of volatile organic compounds, known to the world of science as VOCs. Among other things VOCs are alcohols, volatile deodorant components, aldehydes from furniture, detergent fumes, nicotine, briefly: carbon-based emissions of all kinds.
You could use human noses to sniff VOCs, but sensors in the form of a USB stick are not only more suitable but also immune to attacks of nausea. The Rehau sniffer [1], for example, uses an LED with a color changer to indicate the state of the air in the room.
Pure Air
A tool helps me to read the measured values from the stick. Before you build the software [2], you first need to install the libusb-dev and build-essential packages. After unpacking the zip file to /usr/local/
, the change directory to usb-sensors-linux/trunk/airsensor/
. When you get there, do this:
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