TITLE:

ES&H Manual

 

DOCUMENT ID:

6160 Appendix T2

Ventilated (or Alternate) Entry Procedure

 

 

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:

  1. An attendant is not required.
  2. A permit is not needed, although a record of the pre-entry hazard assessment is required.

 

2.0            Scope

 

Text Box: The Ventilated Entry Procedure may only be used when all of the following conditions are met: 1. The only hazard posed by the PRCS is an actual or potentially hazardous atmosphere. 2. Continuous, forced air ventilation alone is sufficient to maintain the PRCS safe for entry. 3. Workers can enter and work safely in the space. 4. Proof of the above conditions is documented and made available to all entrants. The “Hazard Control” section of the Entry Permit may be used as a guide and record of this hazard assessment.

 

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.

 

Text Box: Note: If entry into a particular space is frequent, it may be advantageous to install a fixed sampling tube or duct to enable future air testing without entry.

 

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.

 

 

 

ISSUING AUTHORITY

APPENDIX AUTHOR

APPROVAL DATE

EFFECTIVE DATE

EXPIRATION DATE

REV.

 

 

 

ESH&Q Division

John Kelly

08/30/06

08/30/06

08/30/09

0

 

This document is controlled as an on line file.  It may be printed but the print copy is not a controlled document.  It is the user’s responsibility to ensure that the document is the same revision as the current on line file.  This copy was printed on 8/19/2009.