14
100106.01
2 Introduction
The Vetus gas detector together with one or two sensors forms a gas detection system
with two different functions.
In the first place for the detection of petrol vapour to prevent the risk of an explosion in
the engine room.
Secondly to detect the poisonous gas carbon monoxide (CO) *) to prevent the forma-
tion of a dangerous and poisonous atmosphere for people.
The danger formed by carbon monoxide is dependent on a time-weighted average. This
means that it is dependent on both the concentration of carbon monoxide and the time
that the carbon monoxide is present.
The concentration of carbon monoxide therefore has influence on the time before the
gas detector gives an alarm.
Both detector functions are carried out at the same time.
*)
Carbon monoxide
(chemical formula CO) is an invisible, colourless and odour-
less gas. It is formed by incomplete combustion in equipment burning organic
fuels such as oil, gas, petrol, coal and wood (so not in electrical installations!).
Incomplete combustion means that there is insufficient oxygen present to allow
good or complete combustion.
When carbon monoxide is breathed in it is taken up by the blood via the lungs and
attaches itself to the red blood cells. Red blood cells transport oxygen through the
body. Because carbon monoxide attaches to red blood cells about 200x more easily
than oxygen it can very easily displace oxygen from the blood and this can therefore
transport less oxygen.
The gas detector can be connected to a 12 Volt or a 24 Volt direct current power sup-
ply.
The gas detector can be used in either continuous or intermittent mode according to
choice, see 3.2.
tIt is recommended that the possible presence of petrol vapour and carbon
monoxide should
always
be checked; even when the ship is not in use!
Therefore, always keep the power supply to the gas detector switched on.
Gas detector PD1000
