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6160
Appendix T2 Ventilated
(or Alternate) Entry Procedure |
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1.0
Introduction
This
procedure
is an abbreviated confined
space entry procedure
that is predicated upon the hazard being known and eliminated by
ventilation. If specific conditions are
met, this alternate procedure
may be used for initial entry
into a permit-required
confined space (PRCS). It may also
be used for re-entries (subsequent to an initial entry
using ES&H Manual Chapter
6160 Appendix T4
General Procedure for Entry into Permit-Required Confined Spaces)
when the entry supervisor determines that the only hazard is potentially unsafe
air.
Two
important differences in entry
requirements under ventilated entry:
2.0
Scope

Monitoring
the atmosphere for oxygen, flammability, and toxicity is an essential part of
the Ventilated Entry Procedure. A qualified individual must be present to
monitor the atmosphere, to notify appropriate staff and
entrants of all readings, and to record the
readings.
If entry into the PRCS is necessary in order to obtain the first set of atmospheric measurements, then
ES&H Manual Chapter
6160 Appendix T4 General Procedure for Entry into Permit-Required Confined
Spaces
must be used to verify that the air is safe. Likewise, if entry
is necessary to install temporary ventilation, General Procedures must
be used for the initial entry.
3.0
Process Steps or
Expectations
Step 1
Verify that
the only hazard present in the PRCS is an
actual or potentially hazardous atmosphere.
This means that no significant chemical, electrical, engulfment,
entrapment, or other hazard is known to exist inside the PRCS. Nor is an “ordinary condition” made more
hazardous by its combination with a confined
space. Ensure there are reliable
means to summon help: test your radio or telephone.
Step 2
If there is an
entrance cover, eliminate all conditions (pressure, heat, smoke, etc.) which
make it unsafe to remove the cover. Then
remove the entrance cover and store it in a safe place.
Step
3
If the space
is below the working surface, guard the entrance using a railing, barricade, or
other temporary means to prevent an accidental fall through the opening and to
prevent foreign objects from falling in.
Step 4
Check the
internal atmosphere with direct reading, calibrated instruments for oxygen
content, flammability, and for any toxic material potentially present. See ES&H Manual Chapter
6160 Appendix T3 Atmospheric Testing of Confined Spaces for more
information. (The characteristics of the
air in this initial test can give you a good indication of the existing or
“natural” processes that may degrade air quality during entry.)
Step 5
Establish
forced-air ventilation so that it ventilates the intended work area, and ensure
that it is maintained until all personnel have left the PRCS. Ensure that ventilation failure will be
indicated by reliable means. If
ventilation fails, evacuate the space immediately.
Step 6
Ensure that
the source of ventilation air is not subject to contamination (e.g., by vehicle
exhaust) and does not increase the hazards in the PRCS. Ensure that ventilation hoses will not hinder
quick escape.
Step 7
Specifically
communicate to each entrant that the conditions have been met for ventilated entry
into a confined
space. Verify that each entrant is
familiar with this procedure
and is able to quickly exit the confined
space if conditions unexpectedly change.
Step 8
Begin the entry
work. Be alert to any change in
conditions or activities that could change the hazards from the initial
assessment.
Step 9
Continue to
check the internal atmosphere regularly with appropriate instrumentation. Document the readings and post them nearby
where they can be seen. A suitable recording
form is in ES&H
Manual Chapter 6160 Appendix T3
Atmospheric Testing of Confined Spaces. If readings indicate out-of-specifications
conditions, evacuate immediately and reassess the situation.

Step 10 
When the entry
is completed, remove all postings of atmospheric measurements and forward the
documentation to the ES&H Division for archiving. The documentation is retained in order to aid
the planning of future entries into this or similar confined
spaces.
Step 11
Remove
barricades if used, and replace the entrance cover if so equipped.
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ISSUING
AUTHORITY |
APPENDIX
AUTHOR |
APPROVAL
DATE |
EFFECTIVE
DATE |
EXPIRATION
DATE |
REV. |
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ESH&Q Division |
08/30/06 |
08/30/06 |
08/30/09 |
0 |
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