General Equipment EP8HL, Руководство оператора

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EP8HL HAZARDOUS BLOWER
FORM GOM7069501, VERSION 1.2
25
CONFINED WORK SPACE BEFORE ALLOWING
PERSONNEL TO ENTER. IT MAY SAVE A LIFE OR
MINIMIZE THE CHANCE OF AN EXPLOSION.
What are the hazards involved when entering and
working in a confined work space?
The atmosphere inside a confined work space can be
extremely hazardous because of the lack of natural air
movement. This lack of natural air movement can
result in the following types of atmospheres:
1) Oxygen deficient atmosphere.
2) Flammable atmosphere.
3) Toxic atmosphere.
What is an oxygen deficient atmosphere?
An oxygen deficient atmosphere has less than 19.5
percent available oxygen for human consumption.
Another definition is an atmosphere with a partial
pressure of oxygen (PO2) of less than 132 mm Hg.
Normal air at sea level contains approximately 21
percent oxygen at a PO2 of 160 mm Hg. Things can
change with altitude. For instance, in Denver,
Colorado, with an altitude of approximately one mile,
normal air contains approximately 21 percent oxygen
at a PO2 of 132 mm Hg. Any atmosphere with less
than 19.5 percent oxygen should not be entered
without an approved, self-contained breathing
apparatus (SCBA).
The oxygen level in a confined work space can also
decease because of the nature of the work being
performed in it. Operations such as welding, cutting or
brazing will decrease the oxygen level in the space.
Certain chemical reactions such as rusting or bacterial
action such as fermentation can also decrease the
oxygen level.
The oxygen level can also be decreased if it is
displaced by another gas such as carbon dioxide or
nitrogen. Total displacement of oxygen by another gas
will result in unconsciousness, followed by death.
THE OXYGEN LEVEL IN A CONFINED SPACE IS A
CRITICAL FACTOR FOR WORKER SAFETY. AN
INSUFFICIENT OXYGEN LEVEL CAN CAUSE
DEATH. AN EXCESSIVE OXYGEN LEVEL CAN
READILY SUPPORT AN EXPLOSION.
What is a flammable atmosphere?
Two factors make a confined work space atmosphere
flammable:
1) The oxygen level present in the space.
Different gases have different flammable ranges. If an
ignition source (ie: flame from a match, a spark from a
direct blow, etc.) is introduced into a confined work
space containing a flammable atmosphere, an
explosion will result.
2) A flammable gas, vapor or dust in the proper
mixture.
An atmosphere containing 23.5 percent or greater
oxygen is referred to as an oxygen rich atmosphere.
These atmospheres will cause flammable materials
such as clothing and hair to burn violently when ignited.
NEVER USE PURE OXYGEN TO VENTILATE A
CONFINED WORK SPACE. VENTILATE WITH A
SUITABLE PORTABLE AIR VENTILATION BLOWER
WITH NORMAL, AMBIENT AIR. TEST UNTIL THE
ATMOSPHERE IS WITHIN PROPER LIMITS.
RETEST AS NECESSARY.
What is a toxic atmosphere?
Most substances such as liquids, vapors, gases, mists,
solids and dusts should be considered hazardous in a
confined work space. Toxic substances can be formed
by the following:
1) While the product is being stored.
A product that is stored in a confined work space can