American Magnetics 430, Инструкции по установке, эксплуатации и обслуживанию

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XII
R
EV
9
A
MERICAN
M
AGNETICS
, I
NC
. F
OREWORD
: G
ENERAL
P
RECAUTIONS
T
REATING
C
OLD
B
URNS
In the event a person is burned by a cryogen or material cooled to
cryogenic temperatures, the following first aid treatment should be given
pending the arrival and treatment of a physician or other medical care
worker:
1. If any cryogenic liquid contacts the skin or eyes, immediately flush the
affected area gently with tepid water (102°F
−
105°F, 38.9°C
−
40.5°C) and
then apply cold compresses.
2. Do not apply heat. Loosen any clothing that may restrict circulation. Apply a
sterile protective dressing to the affected area.
3. If the skin is blistered or there is any chance that the eyes have been
affected, get the patient immediately to a physician for treatment.
H
ANDLING
C
RYOGENIC
L
IQUIDS
Containers of cryogenic liquids are self pressurizing (as the liquid boils
off, vapor pressure increases). Hoses or lines used to transfer these
liquids should never be sealed at both ends (i.e. by closing valves at
both ends).
When pouring cryogenic liquids from one container to another, the
receiving container should be cooled gradually to prevent damage by
thermal shock. The liquid should be poured slowly to avoid spattering
due to rapid boil off. The receiving vessel should be vented during the
transfer.
M
ATERIAL
S
AFETY AT
C
RYOGENIC
T
EMPERATURES
Introduction of a substance at or near room temperature into a cryogenic
liquid should be done with great caution. There may be a violent gas
boil-off and a considerable amount of splashing as a result of this rapid
boiling. There is also a chance that the material may crack or
catastrophically fail due to forces caused by large differences in thermal
contraction of different regions of the material. Personnel engaged in this
type of activity should be instructed concerning this hazard and should
always wear a full face shield and protective clothing. If severe spraying
or splashing could occur, safety glasses or chemical goggles along with
body length protective aprons will provide additional protection.
The properties of many materials at extremely low temperatures may be
quite different from the properties that these same materials exhibit at
room temperatures. Exercise extreme care when handling materials
cooled to cryogenic temperatures until the properties of these materials
under these conditions are known.