User Manual

Safety and occupational health instructions
54
Pos: 10.7 /00005 Ü berschriften/ 1.1 Überschrifte n/1.1 Überschrift en Dewar/11 De war Sicherheits hinweise beim U mgang mit flüssi gem Stic kstoff @ 0\mod _1233751965 302_9.doc @ 5692 @ @ 1
9.2 Safety instructions on the handling of liquid nitrogen
Pos: 10.8 /00005 Ü berschriften/ 1.1 Überschrift en/1.1 Übersc hriften Dewar/11 Dewar Sauersto ffmangel @ 0\ mod_123375 2064958_9.doc @ 5698 @ @ 1
9.3 Oxygen deficiency
Pos: 10.9 /00010 Bedienungsa nleitungen Kapitels ammlungen/Cr yoMill/0020 Cr yo Sicherheits kapitel/0017 Cr yo Kapitel Sauerst offmangel @ 0\mod_12 33907180174 _9.doc @ 5994 @ @ 1
The main components of air according to volumes are as follows:
– Oxygen O2 21 %
– Nitrogen N2 78 %
– Argon Ar 1 %
The gases contained in the atmosphere are not toxic. However, a change in
concentration (in particular changes to the oxygen concentration) may have effects
on life and burns. It is therefore essential for the air breathed in to contain sufficient
oxygen (> 19 %).
Humans cannot detect changes in the composition of air within the time that will
actually be necessary because the components are colourless and odourless.
Pos: 10.10 /0000 5 Überschriften/1 .1.1 Überschri ften/111 Dewar Gefahren @ 0\mod_12339 06093088_9.d oc @ 5946 @ @ 1
9.3.1 Dangers
Pos: 10.11 /0001 0 Bedienungs anleitungen Kapit elsammlunge n/CryoMill/0020 Cr yo Sicherheits kapitel/0019 Cr yo Kapitel Sau erstoffmang el Gefahren @ 0 \mod_1233 907181002_9.doc @ 6001 @ @ 1
A danger of suffocation exists as a result of the normal evaporation of the liquid
nitrogen that pushes out the oxygen in the air. An oxygen deficiency is dangerous
and can cause death through suffocation. The reaction of the organism to oxygen
deficiency will differ greatly depending on the individual. It is not possible to provide
precise and generally applicable information on the symptoms of an oxygen
deficiency.
Example: under normal conditions (20° C; 1013 mbars) 1 l liquid nitrogen
evaporates to produce 680 l nitrogen gas.
Pos: 10.12 /0000 5 Überschriften/1 .1.1 Überschri ften/111 Dewar Urs achen @ 0 \mod_1233 906124198_9.d oc @ 5952 @ @ 1
9.3.2 Causes
Pos: 10.13 /0001 0 Bedienungs anleitungen K apitelsammlunge n/CryoMill/002 0 Cryo Sicherheits kapitel/0021 Cr yo Kapitel Sau erstoffmang el Ursachen @ 0\ mod_123390 7185955_9.doc @ 6064 @ @ 1
An oxygen deficiency may arise during the following work or in the following
conditions:
– Nitrogen as liquid or gas
– Natural evaporation of liquid nitrogen
– Refilling of liquid nitrogen
– Leaks in containers for liquid or gaseous nitrogen
– Defect in the air feed or outlet
– Tipping over of the container
This list is not complete.
Pos: 10.14 /0000 5 Überschriften/1 .1.1 Überschri ften/111 Dewar Empfehlungen @ 0\mod_1 233906148542 _9.doc @ 595 8 @ @ 1
9.3.3 Recommendations
Pos: 10.15 /0001 0 Bedienungs anleitungen Kapit elsammlunge n/CryoMill/0020 Cr yo Sicherh eitskapitel/0018 Cr yo Kapitel Sa uerstoffmang el Empfehlungen @ 0\mod_1 233907181658_ 9.doc @ 6008 @ @ 1
In order to prevent the danger of an oxygen deficiency, the following measures
must be taken.
The vessel:
• must be kept in a vertical position.
• must be provided with a suitable insulating lid.
• must be protected from direct sunlight and may not be set up near heat
sources.