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Publication Number: FHWA-RD-98-180

Safety and Health on Bridge Repair, Renovation and Demolition Projects

APPENDIX F


SAMPLE PERMIT - REQUIRED CONFINED SPACE PROGRAM

Table of Contents

A.
B.
C.

 
Workplace.
  Sewer entry.

Potential hazards.  The employees could be exposed to the following:


Engulfment.

Presence of toxic gases.  Equal to or more than 10 ppm hydrogen sulfide measured as an 8-hour time-weighted average. If the presence of other toxic contaminants is suspected, specific monitoring programs will be developed.

Presence of explosive/flammable gases.  Equal to or greater than 10 percent of the lower flammable limit (LFL).

Oxygen deficiency.  A concentration of oxygen in the atmosphere equal to or less than 19.5 percent by volume.

 

A.  ENTRY WITHOUT PERMIT/ATTENDANT

Certification.  Confined spaces may be entered without the need for a written permit or attendant provided that the space can be maintained in a safe condition for entry by mechanical ventilation alone, as provided in 1910.146(c)(5).  All spaces shall be considered permit-required confined spaces until the pre-entry procedures demonstrate otherwise.  Any employee required or permitted to pre-check or enter an enclosed/confined space shall have successfully completed, as a minimum, the training as required by the following sections of these procedures.  A written copy of operating and rescue procedures as required by these procedures shall be at the work site for the duration of the job.  The Confined Space Pre-Entry Checklist must be completed by the LEAD WORKER before entry into a confined space.  This list verifies completion of items listed below.  This checklist shall be kept at the jobsite for duration of the job.  If circumstances dictate an interruption in the work, the permit space must be re-evaluated and a new checklist must be completed.

Control of atmospheric and engulfment hazards.

Pumps and Lines.  All pumps and lines that may reasonably cause contaminants to flow into the space shall be disconnected, blinded, and locked out, or effectively isolated by other means to prevent development of dangerous air contamination or engulfment.  Not all laterals to sewers or storm drains require blocking; however, where experience or knowledge of industrial use indicates there is a reasonable potential for contamination of air or engulfment into an occupied sewer, then all affected laterals shall be blocked.  If blocking and/or isolation requires entry into the space, the provisions for entry into a permit-required confined space must be implemented.

Surveillance.  The surrounding area shall be surveyed to avoid hazards such as drifting vapors from the tanks, piping, or sewers.

Testing.  The atmosphere within the space will be tested to determine whether dangerous air contamination and/or oxygen deficiency exists.  Detector tubes, alarm only gas monitors, and explosion meters are examples of monitoring equipment that may be used to test permit space atmospheres.  Testing shall be performed by the LEAD WORKER who has successfully completed the gas detector training for the monitor he will use.  The minimum parameters to be monitored are oxygen deficiency, LFL, and hydrogen sulfide concentration.  A written record of the pre-entry test results shall be made and kept at the work site for the duration of the job.  The supervisor will certify in writing, based upon the results of the pre-entry testing, that all hazards have been eliminated.  Affected employees shall be able to review the testing results.  The most hazardous conditions shall govern when work is being performed in two adjoining, connecting spaces.

Entry Procedures.  If there are no non-atmospheric hazards present and if the pre-entry tests show there is no dangerous air contamination and/or oxygen deficiency within the space and there is no reason to believe that any is likely to develop, entry into and work within may proceed.  Continuous testing of the atmosphere in the immediate vicinity of the workers within the space shall be accomplished.  The workers will immediately leave the permit space when any of the gas monitor alarm set points are reached as defined.  Workers will not return to the area until a SUPERVISOR who has completed the gas detector training has used a direct reading gas detector to evaluate the situation and has determined that it is safe to enter.

Rescue.  Arrangements for rescue services are not required where there is no attendant.  See the rescue portion of section B., below, for instructions regarding rescue planning where an entry permit is required. 

 

B. ENTRY PERMIT REQUIRED

Permits.  Confined Space Entry Permit. All spaces shall be considered permit-required confined spaces until the pre-entry procedures demonstrate otherwise.  Any employee required or permitted to pre-check or enter a permit-required confined space shall have successfully completed, as a minimum, the training as required by the following sections of these procedures.  A written copy of operating and rescue procedures as required by these procedures shall be at the work site for the duration of the job.  The Confined Space Entry Permit must be completed before approval can be given to enter a permit-required confined space.  This permit verifies completion of items listed below.  This permit shall be kept at the job site for the duration of the job.  If circumstances cause an interruption in the work or a change in the alarm conditions for which entry was approved, a new Confined Space Entry Permit must be completed.

Control of atmospheric and engulfment hazards.

Pumps and Lines.  All pumps and lines that may reasonably cause contaminants to flow into the space shall be disconnected, blinded, and locked out, or effectively isolated by other means to prevent development of dangerous air contamination or engulfment.  Not all laterals to sewers or storm drains require blocking; however, where experience or knowledge of industrial use indicates there is a reasonable potential for contamination of air or engulfment into an occupied sewer, then all affected laterals shall be blocked.  If blocking and/or isolation requires entry into the space, the provisions for entry into a permit-required confined space must be implemented.

Surveillance.  The surrounding area shall be surveyed to avoid hazards such as drifting vapors from tanks, piping, or sewers.

Testing.  The confined space atmosphere shall be tested to determine whether dangerous air contamination and/or oxygen deficiency exists.  A direct reading gas monitor shall be used. Testing shall be performed by the SUPERVISOR who has successfully completed the gas detector training for the monitor he will use.  The minimum parameters to be monitored are oxygen deficiency, LFL, and hydrogen sulfide concentration.  A written record of the pre-entry test results shall be made and kept at the work site for the duration of the job.  Affected employees shall be able to review the testing results.  The most hazardous conditions shall govern when work is being performed in two adjoining, connected spaces.

Space Ventilation.  Mechanical ventilation systems, where applicable, shall be set at 100 percent outside air.  Where possible, open additional manholes to increase air circulation.  Use portable blowers to augment natural circulation if needed.  After a suitable ventilating period, repeat the testing.  Entry may not begin until testing has demonstrated that the hazardous atmosphere has been eliminated.

Entry Procedures.  The following procedure shall be observed under any of the following conditions:

1.)    Testing demonstrates the existence of dangerous or deficient conditions and additional ventilation cannot reduce concentrations to safe levels;

2.)    The atmosphere tests as safe but unsafe conditions can reasonably be expected to develop;

3.)    It is not feasible to provide for ready exit from spaces equipped with automatic fire suppression systems and it is not practical or safe to deactivate such systems; or

4.)    An emergency exists and it is not feasible to wait for pre-entry procedures to take effect. 

All personnel must be trained.  A self-contained breathing apparatus shall be worn by any person entering the space.  At least one worker shall stand by the outside of the space ready to give assistance in case of emergency.  The standby worker shall have a self-contained breathing apparatus available for immediate use.  There shall be at least one additional worker within sight or call of the standby worker.  Continuous powered communications shall be maintained between the worker within the confined space and standby personnel.  If at any time there is any questionable action or non-movement by the worker inside, a verbal check will be made.  If there is no response, the worker will be moved immediately.  Exception:  If the worker is disabled due to falling or impact, he/she shall not be removed from the confined space unless there is immediate danger to his/her life.  Local fire department rescue personnel shall be notified immediately.  The standby worker may only enter the confined space in case of an emergency (wearing the self-contained breathing apparatus) and only after being relieved by another worker.  Safety belt or harness with attached lifeline shall be used by all workers entering the space with the free end of the line secured outside the entry opening.  The standby worker shall attempt to remove a disabled worker via his or her lifeline before entering the space.

When practical, these spaces shall be entered through side openings -- those within 3 1/2 feet (1.07 m) of the bottom.  When entry must be through a top opening, the safety belt shall be of the harness type that suspends a person upright, and a hoisting device or similar apparatus shall be available for lifting workers out of the space.

In any situation where their use may endanger the worker, use of a hoisting device or safety belt and attached lifeline may be discontinued.

When dangerous air contamination is attributable to flammable and/or explosive substances, lighting and electrical equipment shall be Class 1, Division 1 rated per National Electrical Code and no ignition sources shall be introduced into the area.

Continuous gas monitoring shall be performed during all confined space operations.  If alarm conditions change adversely, entry personnel shall exit the confined space and a new confined space permit issued.

Rescue.  Call the fire department services for rescue.  Where immediate hazards to injured personnel are present, workers at the site shall implement emergency procedures to fit the situation.

 

Sample Entry PermitSample Entry Permit

 

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