Permit Required Confined Space: Guide to Permit Requirements and Safety Procedures

Confined spaces are defined as spaces large enough for workers to enter and perform assigned work but have restricted entry and exit and aren’t intended for continuous employee occupancy. While some require permits due to specific hazards, others don’t.

This article explains the differences between permit required confined spaces and non permit confined spaces, highlighting PRCS requirements, legal and regulatory framework, and safety procedures.

Key Takeaways

• Permit required confined spaces contain hazards, while non-permit spaces have fewer hazards and thus require fewer safety measures to enter.

• A confined space permit confirms the space is safe for entry and outlines conditions, hazards, and safety procedures.

• Entry permits are approved by an entry supervisor after all safety measures and requirements are verified.

• Hazard control methods in permit required confined spaces include ventilation plans, lockout tagout, atmospheric testing, rescue plans, and using PPE.

 

What Constitutes a Permit Required Confined Space (PRCS)

According to the Occupational Safety and Health Administration (OSHA) Standard 29 CFR 1910.146(b), a permit required confined space (PRCS) is a confined space that presents additional hazards requiring specific safeguards. To classify as PRCS, the space must meet the general definition of a confined space, plus one or more of the following hazardous conditions:

1. Hazardous Atmosphere

1. The air inside the space poses a danger due to insufficient oxygen (<19.5%) or excessive oxygen (>23.5%).

2. Presence of flammable gases, vapors, or dust in concentrations that could ignite.

3. Toxic substances exceeding OSHA permissible exposure limits (PELs), such as Hydrogen Sulfide or Carbon Monoxide.

2. Potential for Engulfment

1. The space contains materials (grain, sand, or liquid) that could trap, suffocate, or engulf a person.

3. Internal Configurations

1. The space has structures like sloping walls, inwardly converging walls, or other features that could trap or asphyxiate entrants.

4. Other Recognized Serious Physical Harm Risks

1. Any condition that could cause death or injury, such as unguarded machinery, extreme heat, or live electrical systems.

This designation is what separates a PRCS from a non permit confined space, where these hazards are absent. A permit required confined space is labeled as a "permit space" because entry is regulated by a permit system that involves pre-entry hazard evaluation and adherence to documented permit space entry operation.

Identifying Permit Required Confined Spaces

Recognizing environments prone to permit space hazards allows for proper safety planning before any work begins. Below are some common examples:

• • Construction Sites: Trenches and excavations (dug-out areas for construction or utility work), underground utility access points (tunnels, underground passages, and crawl spaces), building sites, and underground construction projects, tank building, and fabrication/vessel fabrication.

  • Mining and Extraction Operations: Underground mines, shafts, and confined areas within extraction facilities.

  • Utility Sector: Water treatment facilities, electrical substations, wastewater plants, power stations, and telecommunications vaults.

  • Transportation and Shipping: Aircraft maintenance facilities, railway maintenance yards, cargo holds, tanks (storage tanks, silos, and enclosed vessels), and engine compartments on ships, as well as tunnels and underground transportation systems.

  • Manufacturing Industry: Confined storage areas (rooms or spaces designed for storage, such as vaults or storage bins) and enclosed machinery compartments (equipment or machinery with limited access points, such as engine rooms or mechanical enclosures), material hoppers

  • Industrial chemical manufacturing and oil refining: tanks, piping, vessels, reactors, sumps, cooling towers, waste bins, and process columns.

A confined space permit is formal documentation that confirms a PRCS is safe under acceptable entry conditions. This permit must be posted at the entry point or be readily accessible to all involved personnel during the operation. After the work is complete, permits must be retained for at least one year for review and recordkeeping.

What Does OSHA Mean by a “Limited or Restricted Means of Entry and Exit” in the Definition of “Confined Space”?

Picture a ladder leading into a 10-foot-deep tank. It’s not impossible to climb in or out, but it’s also not something you’d want to navigate in an emergency due to its size, location, or other physical obstacles. OSHA focuses on the physical restrictions that could delay escape or rescue in a crisis. These spaces may include manholes, narrow hatches, or spaces that require contortion to enter.

 

What Constitutes a Non Permit Required Confined Space

A non permit required confined space is a confined space that does not contain hazards capable of causing death or serious harm. While it meets the basic criteria of a confined space, it lacks the additional dangers that would require extra precautions. For example:

• • Clean and empty storage tanks with no hazardous residue.

  • Utility vaults or crawlspaces with no hazardous atmosphere.

  • Trenches or excavations with stable walls and no risk of toxic gases.

Non Permit-Required Confined Space Checklist

Before classifying a space as non entry permit required, it is helpful to document findings with a non permit-required confined space checklist. This checklist might include:

1. Air quality measurements showing normal oxygen levels and no harmful substances.

2. Visual inspection for physical hazards or structural risks.

3. Verification that the space is free from materials that could engulf workers.

4. Confirmation of safe equipment conditions (de-energized and locked out).

 

Permit vs Non Permit Confined Space

While all PRCS are confined spaces, not all confined spaces are PRCS. The difference boils down to hazards. A permit required confined space involves dangers that need extra safeguards, such as an entry permit, trained personnel, and monitoring. A non permit confined space, by contrast, doesn’t pose those risks. 

This table summarizes the distinctions between permit required confined spaces and non permit confined spaces, highlighting the varying levels of hazards, requirements, and operational protocols.

 

Is It Possible to Convert a Confined Space Into a Non-permit Required Space?

Yes, it is possible to convert a confined space into a non-permit required space if all the hazards have been eliminated or controlled. For example, the image above shows a worker ventilating a fuel tank to remove toxic gases using a blower. This might reclassify it as non-permit. 

Furthermore, in my experience, disconnecting piping and all sources of energy from the space assists further with declassification, but the Confined Space Supervisor should ask him or herself “What do I gain from declassification?” also, declassification could occur if one of the three confined space criteria can be eliminated. However, maintaining this classification depends on consistent monitoring and compliance with documented procedures under a permit space program.

What Is Required if We Reclassify a Permit Space as a Non-permit Confined Space?

If a permit space is reclassified as a non-permit confined space, it must meet specific criteria outlined in OSHA’s 1910.146 standard. This typically involves reassessing and eliminating any existing hazards, implementing necessary engineering controls, and documenting the reclassification process. If hazards are only temporarily eliminated, during maintenance or a specific task, the space can be reclassified for the duration of the activity. Once the task is complete, and hazards could return, the space must be treated as PRCS again.

 

PRCS Legal and Regulatory Framework

Beyond defining PRCS and non-permit required confined spaces, the OSHA establishes guidelines and standards for PRCS safety. According to the 29 CFR 1910.146 standard, employers are required to:

1. Evaluate the workplace to determine if any confined spaces are PRCS.

2. Develop and implement a written permit space program when PRCS are identified.

3. Inform employees of the presence of PRCS through proper signage, such as permit required confined space signs, or a confined space cover to lock out entryways.

4. Prevent unauthorized entry into PRCS by establishing and regulating employee entry.

A permit space program is required to manage safety in PRCS. It serves as a detailed plan that specifies the procedures and steps needed for safely entering and performing work within PRCS while addressing potential hazards. OSHA mandates that the employer's permit space program include:

• • Hazard Assessment: Outline procedures for identifying and evaluating permit space hazards before any entry.

  • Entry Authorization: Specify how permits are issued and maintained. Entry into PRCS is only allowed when an entry permit is completed and signed by the entry supervisor. 

  • Control Measures: Detail methods for hazard control, including forced air ventilation, isolation of energy sources (lockout/tagout), and use of personal protective equipment (PPE).

  • Entry Roles and Responsibilities: Clearly define the duties of authorized entrants, attendants, and supervisors.

  • Permit Space Entry Procedures: Specify step-by-step procedures for entering, working within, and exiting PRCS safely.

Construction sites have specific regulations, such as the Confined Spaces in Construction Standard (29 CFR 1926 Subpart AA). Other countries and regions also have their own regulations, such as the European Union's Directive 92/57/EEC and the Australian/New Zealand Standard AS/NZS 2865:2001.

Failure to comply with these regulations can lead to penalties, including fines, citations, or even criminal charges. Additional consequences may involve work stoppages, legal liabilities, damage to reputation, and increased insurance premiums, or worse, workers can become fatally injured inside a space.

 

How to Mitigate Hazards and Risks in a Permit Required Confined Space

Permit required confined space hazards and risks include atmospheric, physical, biological, and psychosocial risks. Learn how to mitigate them for a safer work environment.

Atmospheric Hazards

The hazardous atmosphere in PRCS includes a lack of oxygen. Oxygen-deficient environments can cause dizziness, confusion, and even loss of consciousness. Toxic gases, such as carbon monoxide, hydrogen sulfide, or volatile chemicals, are another health hazard. They can lead to respiratory problems, poisoning, or explosions.

To mitigate atmospheric hazards in permit-required confined spaces, implement thorough atmospheric testing before entry. Ensure proper ventilation systems are in place to maintain safe oxygen levels and remove toxic gases. Clear equipment using procedures and give the clearing process time to allow normal levels of oxygen to become present. Use gas detectors to monitor the atmosphere continuously during work.

Physical Hazards

A physical hazard in PRCS is the configuration of a confined space, such as narrow passages, uneven surfaces, or obstacles, which can impede movement and increase the risk of falls, entrapment, or injuries. Another physical hazard is noise. Excessive noise levels in confined spaces can cause hearing damage and communication difficulties, impacting workers' safety and awareness. 

To mitigate physical hazards in permit-required confined spaces, implement measures to eliminate or control hazards such as protruding objects, restricted spaces, moving machinery, or loud noises. Provide appropriate personal protective equipment (PPE) for workers' safety.

Biological Hazards

Biological hazards in permit required confined spaces include mold and bacteria. Damp and poorly ventilated confined spaces can harbor mold, which can trigger allergies, respiratory issues, and other health problems. Contaminated PRCS can host harmful bacteria that may cause infections or diseases, particularly in environments like sewers or wastewater treatment plants. 

To mitigate biological hazards in permit-required confined spaces, implement proper hygiene practices, including regular cleaning and disinfection. Provide workers with appropriate PPE to minimize exposure to biological agents. Establish protocols for safe handling and disposal of biological substances.

Psychosocial Hazards

Stress and claustrophobia are considered to be the top psychosocial hazards in permit required confined spaces. The confined nature of PRCS can induce stress due to restricted movement, fear of incidents, or working under pressure. Individuals with claustrophobia may experience severe anxiety or panic attacks in confined spaces, affecting their ability to work effectively. 

To mitigate psychosocial hazards in permit-required confined spaces, ensure clear communication channels and regular updates on tasks. Provide adequate breaks and support systems to address stress and mental health concerns. Promote teamwork, collaboration, and a positive work environment to reduce psychosocial risks. Even the atmosphere outside of a confined space can affect the atmosphere on the inside, such as equipment being placed near or next to ventilation intake systems, which can pull CO2 or exhaust into the space.

 

Are There Any Resources or Organizations That Provide Assistance in PRCS Compliance?

Yes, there are resources and organizations that provide assistance in PRCS compliance. Occupational Safety and Health Administration (OSHA) offers guidance documents, confined space training materials, and compliance assistance resources. Industry associations like the National Safety Council (NSC) also offer training and support to help you maintain compliance with PRCS regulations.

 

What Is an Entry Permit?

A confined space work involves permit space entry as a formal authorization for individuals to enter a permit required confined space safely. It typically includes detailed entry-related information:

• • Authorized entrants and their roles.

  • Hazards of the confined space.

  • Measures to eliminate or control permit space hazards

  • Emergency response protocols.

  • Validity period for the entry operation.

The employer's permit entry program may also include a checklist for verifying the completion of pre-entry procedures and necessary equipment. Before entering a PRCS, individuals must undergo training on PRCS hazards, safety procedures, and the proper use of PPE. A thorough evaluation of the PRCS should be conducted to identify potential hazards and implement adequate control measures. The permit may require pre-entry tests, such as atmospheric monitoring, to ensure the space is safe for entry.

 

Roles and Responsibilities of Authorized Entrants, Attendants, and Entry Supervisors

There are three key roles in permit space operations: authorized entrants, attendants, and entry supervisors. Each has specific duties to prevent hazards and respond effectively during emergencies:

• • Authorized Entrants: Individuals entering the PRCS to perform tasks. They are responsible for following safety procedures, using PPE, and promptly reporting any changes or hazards observed during entry.

  • Attendants: Individuals stationed outside the PRCS. They monitor the safety of the entrants, maintain communication, and initiate emergency response procedures if necessary.

  • Entry Supervisors: Individuals who approve entry permits and oversee that entry operations remain consistent, ensuring compliance with safety regulations, verifying permits, and coordinating work activities.

 

How Often Should PRCS Training Be Conducted?

PRCS training should be conducted initially for all affected employees, and then periodically thereafter. The frequency of training should be determined by the employer, considering factors such as employee turnover, changes in work practices, and the need for refresher training to ensure ongoing awareness and competency. It should cover hazard recognition, equipment use, specific roles and responsibilities, confined space rescue protocols, and the implementation of the permit space program.

 

FAQs

Is a crawl space a confined space?

A crawl space can be considered a confined space if it is large enough for a person to enter, has limited entry and exit points, and is not designed for continuous occupancy. However, it may only qualify as a permit required confined space (PRCS) if additional hazards, such as poor air quality or electrical risks, are present.

Who is responsible for identifying PRCS in a workplace?

Employers are responsible for identifying PRCS in the workplace. They should conduct thorough assessments to determine which spaces meet the criteria for permit-required confined spaces. This involves considering factors such as configuration, hazards, and the potential for employee exposure.

How long is needed to retain entry permits?

Entry permits should be retained for a specific duration determined by the employer, based on the work being conducted and any applicable regulations or standards. Generally, it is recommended to retain entry permits for a sufficient period to allow for review, reference, and documentation purposes.

How often should PRCS entry procedures be reviewed and updated?

PRCS entry procedures should be reviewed and updated as necessary, especially when there are changes in the PRCS or the work being conducted. It is essential to ensure that procedures reflect current hazards, control measures, and regulatory requirements. Regular reviews and updates help maintain a safe work environment.

How does the standard apply when the opening to a space is very small?

The standard still applies when the opening to a space is small. If the space meets the definition of a confined space and has associated hazards, it may still require permits and compliance with PRCS regulations. The size of the opening does not exempt it from the requirements if other criteria are met.

Is it a permit space entry if the worker only reaches into the space with his arms?

It depends on the circumstances. If the worker's entry meets the definition of a confined space and there are associated hazards that cannot be controlled from outside the space, it may still be considered a permit space entry. Each situation should be evaluated to determine the need for permits and compliance measures.