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  • +49 7131 200064
  • info@imgmbh.de
  • Competent consulting



The exhaust gas of gas-powered internal combustion engines contains various toxic gases, however, according to the legal requirement DGUV79, only the content of carbon monoxide CO must be measured for these engines.

DGUV 79 / BGV D34 - Accident prevention regulation "Use of liquid gas" (EXTRACT)

§37 Vehicles with liquid gas combustion engine (excerpt)

Paragraph (2)

The employer shall ensure that the pollutant concentration in the exhaust gas is checked periodically, but at least every six months, by an authorised technician and that it is adjusted to the lowest achievable value.

Implementation Instructions for § 37 Para. 2

The lowest achievable value can be assumed if the CO content does not exceed 0.1 Vol.% at idling speed with the engine at operating temperature.

An inspection certificate, which must be completed, signed and handed over to the user by the authorized technician, serves as proof that the exhaust gas measurement has been carried out.

Why is it important to measure the CO concentration?

Carbon monoxide CO is a colorless, odorless, tasteless and toxic gas. Carbon monoxide stops the transport of oxygen and therefore carbon monoxide poisoning can lead to death within a short time. The CO concentration emitted by an engine is many times higher than the concentration allowed to be present in a room, because the emissions from the engine are diluted by the air in the room. Thus, the volume of the room also plays a certain role in the level of CO concentration that is present in the room. The lower the CO emissions from the engine, the better for the people present.

Carbon monoxide CO can cause toxic symptom development:

  • 30 ppm = 0.003 vol.%: AGW value = maximum workplace concentration at 8h working time
  • 200 ppm = 0.02 Vol.%: Mild headache within 2-3 hours
  • 400 ppm = 0.04 Vol.%: Headache in forehead area within 1-2 hours, spreads to whole head area within 2.5 - 3.5 hours
  • 800 ppm = 0.08 vol.%: Dizziness, nausea and limb twitching within 45 minutes. Unconsciousness within 2 hours
  • 1600 ppm = 0.16 vol.%: Headache, dizziness and nausea within 20 minutes. Death within 2 hours
  • 3200 ppm = 0.32 vol.%: Headache, dizziness and nausea within 5 - 10 minutes. Death within 30 minutes
  • 6400 ppm = 0.64 vol.%: Headache and dizziness within 1 - 2 minutes. Death within 10 - 15 minutes
  • 12800 ppm = 1.28 vol.%: Death within 1 - 3 minutes

SUMMARY - Exhaust gas measurement on forklifts with gas engine:

  • Semi-annual exhaust gas inspection and measurement of CO carbon monoxide and adjustment of the engine so that the CO value is less than 0.1 Vol% = 1000 ppm.
  • Creation of inspection certificate

Exhaust gas analyzers for CO measurement on forklift trucks / lift trucks with gas engine