Siemens ULTRAMAT 23 Series - Analyzers in Biogas Plants and Hazardous Areas

2.2 Analyzers in biogas plants
DANGER
Danger of poisoning
This device is designed to measure hydrogen sul󹪝de and dihydrogen sul󹪝de, H
2
S)!
Hydrogen sul󹪝de is highly toxic even in small concentrations! The odor threshold for hydrogen
sul󹪝de is very low at 0.02 vpm (20 vpb), but higher concentrations result in numbing of the
olfactory receptors in the nose so that the odor is no longer perceived. Persons exposed to this
gas in concentrations up to 100 vpm for several hours exhibit symptoms of poisoning such as
fatigue, headaches, lack of appetite, lack of concentration, irritation of the mucous
membranes of eyes and respiratory tract, and throat irritations.
Inhalation of H
2
S concentrations of 500 vpm longer than 30 minutes can cause fatal poisoning.
Concentrations above 1 000 vpm cause death within a few minutes, concentrations above
5 000 vpm cause death within a few seconds!
When using this device in plant where there may be high concentrations of H
2
S and you
therefore need to take following continual precautions to prevent the e󹪜ects of poisoning:
• Connect the gas outlet of the analyzer to a gas exhaust unit so that no gas can escape into
the environment!
• Before you begin maintenance on the analyzer, make sure that the H
2
S concentration in the
analyzer is close to 0 vpm. Before beginning work, always 󹪞ush the gas path of the analyzer
and the gas sampler with ambient air or nitrogen for a duration of about 10 minutes .
• Check for leaks in the analyzer at regular intervals!
DANGER
Danger of explosion
This device is used in biogas plants, among other places. When it is used in biogas plants, you
should expect that the sample gas will contain methane, which forms explosive mixtures with
oxygen or air in certain concentrations. These conditions are possible with certain operating
states of the plant.
2.3 Analyzers in hazardous areas
WARNING
Unsuitable device for the hazardous area
Danger of explosion.
• Only use equipment that is approved for use in the intended hazardous area and labelled
accordingly.
Safety instructions
2.3 Analyzers in hazardous areas
ULTRAMAT 23
Equipment Manual, 04/2022, A5E37100388-012 17