H2S - Hydrogen sulphide
Hydrogen sulphide has a very dangerous and foul-smelling gas whose
odour can be felt even at concentrations below 0.1 ppm.
However, it is very important to note that the sense of smell is not
reliable when it comes to warning of hydrogen sulphide since the
olifactory sense even at low gas concentrations will be stunned.
This means that you can not smell the gas
after a while.
If the concentration then rises to levels harmful to
health, one does not notice the danger.
Hygienic threshold limit values:
Level value: 10ppm
Maximum value: 15ppm
If the concentration increases only slightly
above maximum value the gas is irritating to the eyes and at higher
concentrations, it causes irritation of the mucous membranes (respiratory).
Pulmonary edema may occur.
Other symptoms that occur at higher
concentrations are headache, dizziness and impaired motor activity.
Already at 800 ppm only a few minutes'
exposure is deadly.
Very high concentrations will lead to immediate
Hydrogen sulphide detectors are used, among
other things, in the paper industry, chemical industry and of and in
sewage treatment plants.
Hydrogen sulphide gas has a density that is slightly heavier than
the air density, but still very close.
The sensors should therefore be placed at
breathing height, and at the likely leakage locations.
Sulphide in high concentrations is hazardous.
LEL = approximately 4.3%
Since hydrogen sulphide is slightly heavier
than air it may be collected in locations that are low-lying and
therefore cause an explosive atmosphere.
The ignition temperature is relatively low.
Drilling platforms and rigs
Platforms for gas and oil production
Sludge Measurement Activities
Nuclear power plants with heavy water
Water treatment plants
Locations of wells
Installations for oil recovery / recycling
Pulp and Paper Factories