These short videos show artificial H₂ production (up to 385 ppmv) during soil-gas sampling after probe installation by sledge and sliding hammer techniques (no drilling). The location is within a park in the urban area of Cluj-Napoca, where neither geological degassing nor microbiological H₂ generation take place.

Two Dräger electrochemical sensors are used simultaneously. Both are calibrated by Dräger and routinely controlled by using H₂ calibration standards. CO (carbon monoxide) is a proxy of artificial gas generation by mechanical friction. The CO sensor is compensated for cross-sensitivity with H₂.