1.0 PURPOSE
The purpose of this procedure is to provide guidelines for entering and working in confined spaces.
2.0 RESPONSIBILITY
The site supervisor shall be responsible for the implementation of the requirements set forth in this procedure. It should be noted that this is a general procedure and may not address all of the details that should be considered in every instance. It is the responsibility of the project manager to understand the practice of safe confined space procedures or have a competent person in charge of such operations who does.
3.0 REFERENCES
29 CFR 1910.146
NIOSH Publications NO 80-106 – “Criteria for a Recommended Standard…Working in Confined Spaces”
5.0 DEFINITIONS
5.1 Acceptable Entry Conditions – the conditions that must exist in a permit space to allow entry and to ensure that employees involved with a permit-required confined space entry can safely enter and work within the space.
5.2 Attendant – an individual stationed outside the permit space who monitors the authorized entrants and who performs all of the attendant’s duties assigned in this procedure.
5.3 Authorized Entrant – an employee who is authorized by the employers to enter a permit space.
5.4 Blanking or Blinding – the absolute closure of a pipe, line, or duct by fastening a solid plate that completely covers the bore and that is capable of withstanding the maximum pressure of the pipe, line, or duct with no leakage beyond the plate.
5.5 Confined Space – a space that:
1) Is large enough and so configured that employees can bodily enter and perform assigned work;
2) Has limited or restricted means for entry (for example, tanks, vessels, silos, storage bins, hoppers, vaults, and pits); and
3) Is not designed for continuous human occupancy.
5.6 Double Block and Bleed – closure of a line, duct, or pipe by closing and locking or tagging two individual valves and by opening and locking or tagging a drain or vent valve in the line between the two closed valves.
5.7 Emergency – any occurrence, including any failure of hazard control or monitoring equipment, or an event internal or external to the permit space that could endanger the entrants. In these instances, the entrant must leave the confined space and at a minimum, the space conditions must be verified before reentry.
5.8 Engulfment – the surrounding and effective capture of a person by a liquid or finely divided solid substance that can be aspirated to cause death by filling or plugging the respiratory system or that can exert enough force on the body to cause death by strangulation, constriction, or crushing.
5.9 Entry – the action by which a person passes through an opening into a permit-required confined space. The entry includes ensuing work activities in that space and is considered to have occurred as soon as any part of the entrant’s body breaks the plane of an opening into space.
5.10 Entry Permit – written or printed document that is provided by the employer to allow and control entry into a permit space and which contains the information specified in this procedure.
5.11 Entry Supervisor – the person responsible for determining if acceptable entry conditions are present at a permit space where entry is planned, for authorizing entry and overseeing entry operations, and for terminating entry, as required by this procedure.
5.12 Hazardous Atmosphere – an atmosphere that may expose employees to the risk of death, incapacitation, impairment of the ability to self-rescue, injury, or acute illness from one or more of the following causes:
1) Flammable gas, vapor, or mist in excess of 10% of its lower flammable limit (LFL);
2) Airborne combustible dust at a concentration that meets or exceeds its LFL;
3) Atmospheric concentration of oxygen below 19.5% or above 23.5%;
4) Atmospheric concentration in excess of 50.1% of its occupational exposure limit per the MSDS;
5) Any other atmospheric condition that is immediately dangerous to life or health based on the material’s MSDS or other information.
5.13 Hot Work Permit – employer’s written authorization to perform operations, (e.g., cutting, grinding, welding, burning, or heating) capable of providing a source of ignition.
5.14 Immediately Dangerous to Life or Health (IDLH) – any condition that poses an immediate or delayed threat to life or that would cause irreversible adverse health effects or that would interfere with an individual’s ability to escape unaided from a permit space.
5.15 Inerting – the displacement of the atmosphere in a permit space by a non-combustible gas (e.g., nitrogen) to such an extent that the resulting atmosphere is noncombustible. DANGER – this can also lead to an IDLH atmosphere.
5.16 Isolation – the process by which a permit space is removed from service and completely protected against the release of energy and material into space by such means as blanking or blinding; misaligning or removing sections of lines, pipes or ducts; a double block-and-bleed system; lockout or tag out of all sources of energy; or blocking or disconnecting all mechanical linkages.
5.17 Line Breaking – the intentional opening of a pipe, line, or duct that is or has been carrying flammable, corrosive, or toxic material, an inert gas, or any fluid at a volume, pressure, or temperature capable of causing injury.
5.18 Non-Permit Confined Space – a confined space that does not contain or, with respect to atmospheric hazards, have the potential to contain any hazard capable of causing death or serious physical harm.
5.19 Oxygen-Deficient Atmosphere – an atmosphere containing less than 19.5% oxygen by volume.
5.20 Oxygen-Enriched Atmosphere – an atmosphere containing more than 23.5% oxygen by volume.
5.21 Permit-Required Confined Space (PRCS or permit space) – a confined space that has one or more of the following characteristics:
1) Contains or has the potential to contain a hazardous atmosphere.
2) Contains a material that has the potential for engulfing an entrant;
3) Has an internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or by a floor which sloped downward and tapers to a smaller cross-section; or
4) Contains any other recognized serious safety or health hazard.
5.22 Permit-Required Confined Space Program (Permit Space Program) – employer’s overall program for controlling and, where appropriate, for protecting employees from permit space hazards and for regulating employee entry into permit spaces.
5.23 Permit System – employer’s written procedures for preparing and issuing permits for entry and for returning the permit space to service following the termination of entry.
5.24 Prohibited Condition – any condition in a permit space that is not allowed by the permit during the period when the entry is authorized.
5.25 Rescue Service – personnel designated to rescue employees from permit spaces.
5.26 Retrieval System – the equipment (including a retrieval line, chest or full-body harness, wristlets, if appropriate, and a lifting device or anchor) used for non-entry rescues of persons from permit spaces.
5.27 Testing – the process by which the hazards that may confront entrants of a permit space are identified and evaluated. Testing includes specifying the tests that are to be performed in the permit space. All testing shall be conducted with a properly calibrated and maintained air monitoring instrument. The person performing the test must be properly trained on the use of the instrument.
6.0 PROCEDURE
6.1 Signage
6.1.1 If the workplace contains permit spaces, exposed employees shall be informed by posting danger signs or by any other equally effective means of the existence, location, and danger posed by the permit spaces.
6.1.2 A sign reading: DANGER—PERMIT REQUIRED CONFINED SPACE, DO NOT ENTER or other similar languages shall be posted at the entrance to space(s).
6.2 Classification Of Non-Permit Confined Space
6.2.1 A confined space classified as a permit-required confined space may be re-classified as a non-permit confined space under the following conditions:
6.2.1.1 If the confined space poses no actual or potential atmospheric hazards and if all hazards within space are eliminated without entry into the space.
6.2.1.2 The confined space may remain classified as a non-permit confined space for as long as the non-atmospheric hazards remain eliminated.
6.2.1.3 If it is necessary to enter the space to eliminate hazards, such entry shall be under the requirements for entry into a Permit Confined Space. If testing and inspection during the entry demonstrate that the hazards within space have been eliminated, the space may be classified as a non-permit confined space.
Note: Control of atmospheric hazards through forced air ventilation does not constitute the elimination of the hazards.
6.2.1.4 The site manager re-classifying the confined space shall document the basis for determining that all hazards in a permit space have been eliminated, through a certification that contains the date, the location of the space, and the signature of the person making the determination.
6.2.1.5 If hazards arise within a permit space that has been declassified to a non-permit space, each employee in the space shall exit the space immediately. Space shall be re-evaluated to determine whether it shall be reclassified to a permit-required confined space.
6.3 Entry Requirements – Permit-Required Confined Space
6.3.1 All entries into permit-required confined spaces shall be carried out in strict accordance with the following requirements.
6.3.2 Only trained, qualified, designated persons may enter a Permit-Required Confined Space. This includes only the Authorized Entrants, Attendants, Entry Supervisor, and the person responsible for atmospheric monitoring if other than the above.
6.3.3 Any conditions making it unsafe to remove the cover of the permit space shall be eliminated before the cover is removed.
6.3.4 When entrance covers are removed, the opening shall be promptly guarded by a railing, temporary cover, or other temporary barriers that will prevent an accidental fall through the opening and that will protect each employee working in the space from foreign objects entering the space. The entrants must be protected from outside hazards to assure that pedestrians, vehicles, etc. do not pose a threat to the entrants.
6.3.5 Before an employee enters the space, the internal atmosphere shall be tested with a calibrated direct-reading instrument. Authorized entrants shall have the opportunity to participate in the calibration and monitoring process. The permit space shall be monitored for the following conditions, in the following order:
6.3.5.1 Oxygen content
6.3.5.2 Flammable gases and vapors
6.3.5.3 Potential toxic air contaminants
6.3.6 Employees or their representatives are entitled to request additional monitoring at any time.
6.3.7 There may be no hazardous atmosphere present within the space whenever any employee is inside the space.
6.3.8 Continuous forced-air ventilation shall be used according to the following guidelines:
6.3.8.1 An employee may not enter the space until the forced air ventilation has eliminated any hazardous atmosphere.
6.3.8.2 The forced-air ventilation system shall be so directed as to ventilate the immediate areas where an employee is or will be present within the space and will continue until all employees have left the space; and
6.3.8.3 The air supply for the forced-air ventilation shall be from a clean source and may not increase the hazards in the space.
6.3.9 The atmosphere within the space shall be periodically tested as necessary to ensure that the continuous forced-air ventilation is preventing the accumulation of a hazardous atmosphere.
6.3.10 If a hazardous atmosphere is detected during entry:
6.3.10.1 Each employee shall leave the space immediately;
6.3.10.2 Space shall be evaluated to determine how the hazardous atmosphere developed; and
6.3.10.3 Measures shall be implemented to protect employees from the hazardous atmosphere before any subsequent entry takes place.
6.3.11 Prior to entry by any employee, the entry supervisor will verify that the space is safe for entry and that the measures outlined above have been taken. This verification will be in the form of a written permit that contains, as a minimum, the date, the location of the space, and the signature of the person providing the certification (permit). The Permit shall be executed before entry and shall be made available to each employee entering the space.
6.3.12 Nitro Construction Services shall review entry operations when there is reason to believe that the measures taken under this program may not protect employees, and the program shall be revised to correct deficiencies before subsequent entries are authorized. Examples of circumstances requiring a review of this program are any unauthorized entry of a permit space, the detection of a permit space hazard not covered by the permit, the detection of a condition prohibited by the permit, the occurrence of an injury or near-miss during entry, and employee complaints about the effectiveness of the program.
6.4 Contractor Entry Into PRCS
As a contractor retained to perform permit space entry operations on host employer sites, for each site Nitro Construction Services will:
6.4.1 Obtain any available information regarding permit space hazards and entry operations from the host employer;
6.4.2 Coordinate entry operations with the host employer, when both host employer, Nitro Construction Services, or other contract personnel will be working in or near permit spaces.
6.4.3 Inform the host employer of the permit space program that Nitro Construction Services will follow, and of any hazards confronted or created in permit spaces either through a debriefing or during the entry operation.
6.5 Acceptable Entry Condition-Atmosphere
Entry into a PRCS is acceptable only if the following atmospheric conditions are met:
6.5.1 Flammable gas, vapor, or mist is less than 10% of its lower flammable limit (LFL);
6.5.2 Airborne combustible dust concentration is less than its LFL (this condition may be approximated as a condition in which the dust obscures vision at a distance of five feet or less);
6.5.3 Atmospheric concentration of oxygen must be within the range of 19.5% to 23.5%;
6.5.4 Atmospheric concentration of any substance for which a dose or permissible exposure limit (PEL) is published in Subpart G, “Occupational Health and Environmental Control,” or in Subpart Z, “Toxic and Hazardous Substances” of 29 CFR 1910 must not be present above the PEL, and
6.5.5 No other atmospheric condition that is immediately dangerous to life or health may be present.
6.6 Isolation
The permit space will be removed from service and completely protected against the release of energy and material into space by such means as: blanking or blinding; misaligning or removing sections of lines, pipes, or ducts; a double block-and-bleed system; lockout or tag out of all sources of energy; or blocking or disconnecting all mechanical linkages.
6.7 Purging, Inerting, Flushing, Or Ventilating
Environmental control within a PRCS will be accomplished by purging, inerting, flushing, and/or ventilation. The method or combination of methods will be selected based on the hazard evaluation:
6.7.1 Exhaust systems shall be designed to protect workers in the surrounding areas;
6.7.2 If the potential for flammable atmospheres exists, all lighting and electrical equipment used in the operation will be explosion-proof.
6.7.3 After initial purging and ventilation have been performed, additional testing as described in Section 6.0 above will be performed to ensure that the hazardous atmosphere has been abated.
6.7.4 The ventilation system will be such that it can dilute the atmosphere below the PEL and/or 10 percent of the LFL.
6.8 Testing
Testing and monitoring will be used to evaluate conditions in the PRCS any time entry operations will be conducted. Testing will be accomplished with properly calibrated instruments in accordance with the following guidelines:
6.8.1 Conditions will be tested in the PRCS to determine if acceptable entry conditions exist before entry is authorized to begin;
6.8.2 The PRCS will be monitored as necessary to determine if acceptable entry conditions are being maintained throughout the entry operation; and
6.8.3 When tests for atmospheric hazards are conducted, oxygen will always be tested first, followed by tests for combustible gases and vapors, and then for toxic gases and vapors.
6.9 Permit System
6.9.1 Prior to entry into the PRCS, the entry supervisor will document that required measures have been completed. This documentation will be in the form of an executed entry permit.
6.9.2 Before entry begins, the entry supervisor designated on the permit shall sign the entry permit for authorized entry.
6.9.3 The completed permit will be made available at the time of entry to all authorized entrants by posting it at the entry portal.
6.9.4 The duration of the permit will not exceed the time required to complete the assigned job or task.
6.9.5 The entry supervisor will terminate the entry and cancel the entry permit when:
6.9.5.1 The entry operations covered by the permit have been completed; or
6.9.5.2 A condition not allowed under the entry permit arises in or near the permit space.
6.9.6 Nitro Construction Services will retain each canceled permit for at least one year. Any problems encountered during entry operation will be noted on the Permit.
6.10 Training
6.10.1 All employees authorized to enter and work in PRCSs shall be trained before assignment to such duties, when there is a change in assigned duties, and whenever a change in PRCS operations results in exposure to a new hazard.
6.10.2 Additional training will be required if there is reason to believe that there is a deviation from PRCS procedures or if inadequacies in the employee’s knowledge of these procedures are noted.
6.10.3 The training will include as a minimum:
• Hazard recognition
• Communication
• Protective Equipment
• Lock-out/Tag-out Procedures
• Respiratory Protection
• Self-Rescue
• Permit System
6.10.4 In addition to the above, the attendant must be trained in the following:
• Tracking the number of entrants
• Effects of hazard exposure
• Monitoring multiple spaces
• Emergency Procedures as they pertain to the attendant
• Rescue procedures.
6.10.5 A written certification indicating the above training has been accomplished will be provided for each employee who will participate in an entry operation. The certification will contain each employee’s name, the signatures or initials of the trainers, and dates of the training.
6.11 Duties of Authorized Entrants
6.11.1 Authorized entrants shall be designated craft and supervisory personnel assigned to perform work inside a Permit Required Confined Space.
6.11.2 Knows the hazards that may be encountered during entry, including information on the mode of entry, signs or symptoms, and consequences of exposure;
6.11.3 Knows the proper use of equipment provided for entry operation;
6.11.4 Communicates with the attendant as necessary to enable the attendant to monitor entrant status and to enable the attendant to alert entrants to the need of evacuating the space.
6.11.5 Alert the attendant whenever:
6.11.5.1 The entrant recognizes any warning sign or symptoms of exposure to a dangerous situation; or
6.11.5.2 The entrant detects a prohibited condition.
6.11.6 Exit from the PRCS as quickly as possible whenever:
16.6.1 An order to evacuate is given by the attendant or the entry supervisor;
16.6.2 The entrant recognizes any warning sign or symptoms of exposure to a dangerous situation;
16.6.3 The entrant detects a prohibited condition; or
16.6.4 An evacuation alarm is activated.
6.12 Duties of Attendants
6.12.1 Authorized attendants shall be designated craft personnel assigned this responsibility.
6.12.2 Know the hazards that may be encountered during entry, including information on the mode of entry, signs or symptoms, and consequences of exposure;
6.12.3 Is aware of possible behavioral effects of hazard exposure in authorized entrants;
6.12.4 Continuously maintains an accurate count of authorized entrants in the PRCS and ensures that only authorized entrants are in the space;
6.12.5 Remains outside the PRCS during entry operations until relieved by another attendant;
6.12.6 Communicates with authorized entrants as necessary to monitor entrant status and to alert entrants of the need to evacuate the space.
6.12.7 Monitors activities inside and outside the space to determine if it is safe for entrants to remain in the space and orders the authorized entrants to evacuate the PRCS immediately under any of the following conditions:
6.12.7.1 If the attendant detects a prohibited condition;
6.12.7.2 If the attendant detects the behavioral effects of hazard exposure in an authorized entrant;
6.12.7.3 If the attendant detects a situation outside the space that could endanger the authorized entrants; or
6.12.7.4 If the attendant cannot safely perform all of his assigned duties during the entry operation.
6.12.8 Summons rescue and other emergency services as soon as the determination is made that authorized entrants may need assistance to escape from PRCS hazards.
6.12.9 Takes the following actions when unauthorized persons approach or enter the PRCS while entry is underway:
6.12.9.1 Warns unauthorized persons to stay away from the PRCS;
6.12.9.2 Advised unauthorized persons that they must exit immediately if they have entered the PRCS; and
6.12.9.3 Informs authorized entrants and entry supervisor if unauthorized persons have entered the PRCS.
6.12.10 Performs non-entry rescues. The attendant may also enter the PRCS during a rescue effort but only if:
6.12.10.1 He has been replaced on the outside by another qualified person;
6.12.10.2 He is properly trained in rescue procedures; and
6.12.10.3 He has the proper personal protective equipment (PPE) and other equipment needed to conduct a safe rescue effort.
6.12.11 The attendant may perform no duties that will interfere with his primary duty to monitor and protect the authorized entrants.
6.12.12 If the attendant is to monitor more than one entrance, special provisions must be covered in the Job Safety Analysis (JSA) that will address all aspects of responding to an emergency. If an emergency occurs in one space and the attendant will be focusing attention to that emergency, all spaces being monitored by this attendant must be evacuated.
6.13 Duties Of Entry Supervisors
6.13.1 Entry supervisor shall be a designated Nitro Construction Services supervisor at the job site.
6.13.2 Knows the hazards that may be encountered during entry, including information on the mode of entry, signs or symptoms, and consequences of exposure.
6.13.3 Verifies by checking that the appropriate entries have been made on the permit and that all procedures and equipment specified by the permit are in place before endorsing the permit and allowing the entry to begin.
6.13.4 Terminates the entry and cancels the permit as required above.
6.13.5 Verifies that rescue services are available and that the means for summoning them are operational.
6.13.6 Removes unauthorized individuals who enter or who attempt to enter the permit space during entry operations.
6.13.7 Determines whenever responsibility for PRCS entry operation is transferred and, at intervals dictated by the hazards and operations performed within the space, that entry operations remain consistent with terms of the entry permit and that acceptable entry conditions are maintained.
6.13.8 Reviews and revises entry procedures when and where conditions change and/or activities indicate a change in protective measures. This review shall take place prior to subsequent entries.
6.13.9 Investigates and corrects situations where an unauthorized entry into a PRCS occurs or additional hazards are identified but not indicated on the permit. In the latter, the permit shall be pulled and entry terminated until the hazards are indicated and adequately addressed.
6.14 Rescue And Emergency Services
The responsibility for emergency rescue services may vary by site. Nitro Construction Services employees may perform an emergency rescue services if appropriately trained or outside services may be contracted to perform emergency rescue.
When outside services are contracted to provide emergency rescue for permit confine spaces, the outside service must be given the opportunity to examine the entry site, practice rescue, and decline as appropriate. If the client host rescue team provides this service, it must be agreed to in contract language.
Rescue operations requiring entry into the PRCS are to be performed by the designated rescue team only. Rescue team members shall comply with the following requirements:
6.14.1 Each member of the rescue team will be provided with and trained to properly use the PPE and rescue equipment necessary for making rescues from confined spaces.
6.14.2 Each member of the rescue team will be trained to perform his assigned rescue duties and will also receive the training required for authorized entrants.
6.14.3 Each member of the rescue team will practice making permit space rescues at least once every 12 months by means of simulated rescue operations in which they remove dummies, mannequins, or actual persons from actual PRCSs or representative PRCSs. Representative spaces will simulate the actual types of PRCSs from which rescues may occur in terms of opening size, configuration, and accessibility.
6.14.4 Each member of the rescue team will be trained in basic first aid and cardiopulmonary resuscitation (CPR). At least one member of the rescue service team will hold a current certification in first aid and in CPR.
6.14.5 To facilitate non-entry rescue, retrieval systems or methods will be used whenever an entrant enters a PRCS unless the retrieval equipment would increase the overall risk of entry or would not contribute to the rescue of the entrant. The retrieval system will meet the following requirements:
6.14.5.1 Each authorized entrant will use a chest or full-body harness, with a retrieval line attached at the center of the entrant’s back, near shoulder level, or above the entrant’s head.
6.14.5.2 Wristlets may be used in lieu of the chest or full-body harness if it can be demonstrated that the use of a chest or full-body harness is impractical or creates a greater hazard and that the use of wristlets is the safest and most effective alternative.
6.14.5.3 The other end of the retrieval line will be attached to a mechanical device or fixed point outside the PRCS in such a manner that rescue can begin as soon as the rescuer becomes aware that it is necessary.
6.14.5.4 A mechanical device will be available to retrieve personnel from vertical-type PRCSs more than five feet deep.
6.14.6 For IDLH entries provisions shall be made to have rescue services at the site.
7.0 PROGRAM REVIEW
7.1 The confined space entry program will be reviewed within one year of implementation and will be revised as necessary.
8.0 Appendices
NCS Form 021 – Confined Space Entry Permit