What is a Permit Required Confined Space vs. a Non-Permit One?

Imagine climbing into a small, enclosed space at work, not knowing if the air you’re breathing is toxic or if there’s a hidden danger waiting. This is the reality for many workers who enter confined spaces, and understanding the difference between permit-required confined spaces and non-permit confined spaces can be the difference between life and death.

In this blog, we’ll break down these two types of spaces and share simple steps to stay safe and compliant with OSHA standards.

What Is OSHA's Confined Space Definition?

Under §1910.146(b), OSHA defines a confined space as a space that:

• Is large enough and so configured that an employee can bodily enter and perform assigned work,
• Has limited or restricted means of entry or exit, AND
• Is not designed for continuous employee occupancy.

OSHA further divides its definition of confined spaces into those that require an entry permit and those that don't.

Confined Space Statistics

Confined spaces pose significant risks, with OSHA reporting that approximately 100 fatalities happen every year in the United States due to confined space incidents. These deaths often result from hazardous atmospheres, including toxic gases or oxygen-deficient environments, accounting for nearly 60% of such incidents. Alarmingly, over half of these fatalities involve rescuers untrained or unprepared for the dangers of confined spaces. Industries like construction, manufacturing, and utilities are particularly vulnerable, where confined spaces such as tanks, silos, and manholes are common. These statistics underscore the critical need for proper training, hazard assessments, and compliance with safety regulations to prevent tragic outcomes.

What Is a Permit-Required Confined Space vs. a Non-Permit Space?

Essentially, the difference between a permit-required confined space and a non-permit space is whether there are hazards inside.

There are a few circumstances that make a confined space permit-required. An entry permit is required when the "confined space has one or more of the following characteristics:

• Contains (or has the potential to contain) a hazardous atmosphere,
• Contains a material that has the potential for engulfment of an entrant,
• Has an internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or by a floor which slopes downward and tapers to a smaller cross-section, OR
• Contains any other recognized serious safety or health hazard."

A non-permit confined space is defined as a confined space that does not contain (or, for atmospheric hazards, have the potential to contain) any hazard capable of causing death or serious physical harm.

What Are OSHA's Confined Space Requirements?

There are actually three OSHA confined space standards: General Industry (§1910.146), Construction (§1926 Subpart AA), and Shipyard (§1915 Subpart B).

The confined space regulations in each industry are similar, with General Industry establishing the broad requirements and the Construction and Shipyard standards getting specific on unique circumstances encountered in those environments.

When a workplace has a confined space, an employer is required to do a few things in order to comply with the appropriate standard.

And since confined space work is often performed by contractors, it's worth noting that the confined space standard differentiates between the duties of host employers (who own the building or property), the controlling employer (who arranges for the contractor to be brought in), and the entry employer (who comes on-site and performs the work).

Evaluate the Confined Space for Hazards

Employers must evaluate any confined space for hazards, including (but not limited to) the atmospheric, engulfment, or configuration hazards specified in the definition.

Atmospheric hazards cover any conditions that expose employees to risk of death, incapacitation, impairment to self-rescue, injury, or acute illness. That can include:

• Flammable gas, vapor, or mist in excess of 10% of its lower flammable limit (LFL)
• Airborne combustible dust at a concentration that meets or exceeds its LFL
• Oxygen concentration below 19.5% or above 23.5%
• Hazardous substances with an established permissible exposure limit (PEL)
• Any other atmospheric condition that is immediately dangerous to life or health (IDLH)

Engulfment hazards are liquids or finely divided "flowable solids" (like grain or dirt) that can cause death or injury by aspiration, strangulation, constriction, or crushing.

If, at some point, the confined space's use or configuration changes, then the employer is required to reevaluate the space's hazards and classification.

Get a Permit (If Necessary)

If the employer finds hazards in the space that merit an entry requirement, then they're required to get a permit before anyone enters the space.

Inform Employees of the Risk

OSHA requires employers to warn potentially exposed employees about the existence and location of the permit-required confined space, as well as the dangers it poses.

This requirement can be met with signs "or by any other equally effective means."

Implement Safety Controls

Permit-required confined spaces have hazards that have not been eliminated, but that doesn't mean employers shouldn't control those hazards. In fact, it's required.

The exact requirements depend on the specific hazards, the work being performed, the industry-standard being followed, and more.

A few examples of possible safety controls include:

• Taking effective measures to prevent entry
• Developing and implementing a written permit space program
• Erecting a temporary barrier when entrance covers are removed to prevent accidental entry or falling objects
• Performing pre-entry atmospheric testing
• Using forced air ventilation to eliminate atmospheric hazards
• Providing PPE, ingress/egress equipment, and other necessary equipment
• Arranging for an outside attendant to monitor and assist the entry worker
• Developing a rescue plan

Train Workers Who Will Enter

The confined space requirements include worker training because the confined space standard is a lot more complicated than you can learn in a blog article, and compliance can be a matter of life and death.

Employers must provide training to each affected employee before they begin their duties, any time there's a change in permit space operations that affects hazard exposure, and whenever they suspect inadequate knowledge on an employee’s part.

Although the standard doesn't establish a required frequency, many employers choose to require regular refresher training to help employees stay knowledgeable about the rules.

Can You Change Your Confined Space Classification?

A permit-required confined space can be reclassified as a non-permit space if you eliminate the potential hazards.

This means you've:

• Tested, inspected, and confirmed a lack of actual or potential atmospheric hazards
• Eliminated other potential hazards without entry into the space
• Documented the basis for determining a lack of hazards with a signed certification
• Made the certification available to all employees entering the space

For the purpose of confined space classification, atmospheric hazards cannot be considered "eliminated" through forced air ventilation.

Once a confined space is reclassified, it can remain non-permit for as long as non-atmospheric hazards remain eliminated.

How Often Should Confined Spaces Be Re-Assessed?

Confined spaces should be re-assessed:

• Periodically: At regular intervals based on workplace policies and OSHA requirements.
• After any changes: When there are modifications to the workspace, processes, or conditions that could introduce new hazards.
• Following incidents: If an accident, near-miss, or hazardous event occurs.
• Before each entry: For permit-required spaces, atmospheric testing and hazard evaluations should be performed before allowing workers to enter.

A consistent re-assessment schedule ensures ongoing compliance and helps maintain worker safety.

Meet Confined Space Training Requirements Online

Part of OSHA's confined space standards is a mandatory training requirement.

Online training with an OSHA-authorized training provider like us can be an effective and convenient way to keep up with OSHA's confined space training requirements (among others). Employees can take the training at their own pace for the best comprehension, and we'll make sure they understand the key points with assessment questions.

We offer courses on both the General Industry Confined Space standard and the Construction Confined Space standard. Enroll today!