Safety Measures When Working With Nitrogen - Leica EM ACE600 Operating Manual

2.4.5 Safety measures when working with nitrogen

The volume of the LN
please bear in mind LN
escapes at very low temperature from the boiling LN
as cooled elements (e.g. pipes, valves, hoses, containers or stoppers) can cause
severe frost bite and burns to the skin and eyes.
When LN
2
1 m3 of GN
of nitrogen evaporate (e.g. when transferring LN
ventilated.
Removing LN
where it will evaporate rapidly and safely.
GN is odorless and tasteless and will be inhaled like air. GN
2
high GN
2
produces immediate fainting and deep unconsciousness without any previous
symptoms.
When there is doubt about the adequacy of ventilation, use an oxygen analyzer (0
to 25% scale) to check for oxygen. The content of oxygen must not drop below
18%. If an unconscious person stays in a low oxygen environment then death may
occur. If breathing stops, apply artificial respiration at once and notify doctor and
ambulance immediately!
For the reasons given above, never put LN
chamber. The evaporation rate from Dewar vessels can rise to several liters a day
if they are defective due to improper handling or to natural wear over many years
of use.
Always keep the working area well ventilated.
Bring objects at room temperature carefully into contact with LN
insulating gas layer is formed preventing a large transfer of heat. During this initial
period little LN
occur unexpected strong boiling and spurting of LN
In the case of burns from LN
plenty of water at hand temperature. For serious burns arrange for a skin specialist
to see them at once.
In the case of LN
temperature and arrange for an eye specialist to see it at once.
Never use glass Dewar vessels in the lab (especially glass Dewars larger than 2
liters capacity) without complete metal envelope: Glass Dewars often burst for no
obvious reason or due to unintentional mishandling (e.g. contact with metal
instruments etc.). Never work without open protective glasses when using LN
glass Dewar.
Operating Manual Leica EM ACE600
Dewar is 25 l. When working with liquid nitrogen (LN
2
is extremely cold. It boils at -196 °C. Nitrogen gas (GN
2
evaporates, it expands in a ratio of 1:700. 1 liter LN
. Care should therefore be taken to ensure that when large quantities
2
waste: dump LN
2
content in the air (> 78%) reduces the oxygen-content (< 21%) and
evaporates. However, once the object has cooled down there may
2
2
affecting the eyes, rinse immediately with water at hand
2
Version 01/19
), the room should always be well
2
into an outdoor pit or container filled with gravel,
2
Dewars in a closed storage room or
2
.
2
splashes, rinse the affected skin immediately with
. Both LN and GN
2 2 2
produces almost
2
is non-toxic, but a
2
. Initially an
2
)
2
)
2
as well
in a
2
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