Abstract: A wearable CO2 monitor and stale air dosimeter comprising a power supply with rechargeable battery and battery charger, an accurate CO2 sensor, a fast-reacting CO2 sensor, programmable control circuitry, and a user interface for presenting results and indications. The accurate CO2 sensor provides CO2 levels which are used to compute staleness levels and further accumulated as a staleness dose. The fast-reacting CO2 sensor alerts the user to changes in CO2 levels and allows the accurate CO2 sensor to be powered down during periods when CO2 levels are stable.

Abstract: A sensing device comprising a battery, sensing devices, programmable controller, memory and user interface capable of displaying a QR code. Code running in the programmable device for recording sensor values and encoding them into a device data string and converting the string into a web site address for requesting a report. A web site with code for decoding the query string, appending user supplied data and time information, and generating a report web page presenting the recorded sensor values.