NETZSCH LFA 447 Nanoflash, Руководство по эксплуатации

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General Information
LFA 447
TM
01/09 J:\LFA447\CHAPTER1.DOC
7
HEALTH HAZARDS
Asphyxia
Nitrogen, although non-toxic, can constitute an asphyxiation
hazard through the displacement of the oxygen in the
atmosphere. The potential for this type of hazard is significant
because of the widespread use of nitrogen as a purging or
blanketing gas in chemical, metallurgical, and other industrial
operations and because neither nitrogen gas nor oxygen depletion
are detectable by the normal human senses. Unless adequate
precautions are taken, persons can be exposed to oxygen-deficient
atmospheres if they enter equipment or areas which have
contained or have been purged with nitrogen.
Oxygen is required to support life and its volume concentration in
the atmosphere is normally 21%. At normal atmospheric pressure
(760 mm Hg), persons may be exposed to oxygen concentrations
of 18% by volume (equivalent to a partial pressure of 135 mm Hg),
or even less, without adverse effects. However, the response of
individuals to oxygen deprivation varies considerably. The
minimum oxygen content of breathing atmosphere should be 18%
by volume (at normal atmospheric pressure), but to ensure a wider
margin of operational safety, it is recommended that persons not
be exposed to atmospheres in which the oxygen concentration is,
or may become, less than 20% by volume.
Symptoms of oxygen deprivation, such as increased pulse and
breathing rate, fatigue and abnormal perceptions or responses,
may be apparent at an oxygen concentration of 16%.
Permanent brain damage or death may result from breathing
atmospheres containing less than 10% oxygen. Initial symptoms
include nausea, vomiting and gasping respiration. Persons
exposed to such atmospheres may be unable to help themselves or
warn others of their predicament. The symptoms are an
inadequate warning of the hazard.
BREATHING A PURE NITROGEN ATMOSPHERE WILL PRODUCE
IMMEDIATE LOSS OF CONSCIOUSNESS AND ALMOST IMMEDIATE
DEATH.
Cold burns
Liquid nitrogen and cold nitrogen vapors or gases can produce
effects on the skin similar to a burn. Unprotected parts of the
body coming into contact with uninsulated parts of the equipment
may also stick fast (because all available moisture is frozen) and
the flesh may be torn on separation.