Post #6 – Why is it paramount that you understand the OSHA confined space definition? Because OSHA regulates entry into permit-required confined spaces, and the only way to know if you have a permit-required confined space is to first understand whether or not you are even dealing with a confined space as defined by OSHA in their standards.

As you dig deeper into the OSHA confined space standards, you will come to realize that, in addition to the common question of what is the OSHA definition of a confined space, you will no doubt find yourself asking several other questions, such as:

• What does OSHA mean by “bodily enter”?
• Does a “limited or restricted means for entry or exit” mean there is only one way in and out of the confined space? and,
• If there are no hazards present in the space, does that mean it does not meet the definition of a confined space?

Answers to these questions and more are forthcoming in this blog post.

OSHA’s Confined Space Definitions

The OSHA definition of a confined space appears in both the 1910.146 confined space standards for general industry (see section (b) – definitions), as well as in the 1926 Subpart AA confined space standards for construction (see 1926.1202 – definitions). These two definitions are essentially the same, so we will focus on the definition of a confined space found in the general industry rules for now.

According to the OSHA definition of a confined space found in 1910.146(b), a confined space is characterized by three distinct criteria. The standard states that a confined space is a space that:

(1) Is large enough and so configured that an employee can bodily enter and perform assigned work; and,

(2) Has limited or restricted means for entry or exit (for example, tanks, vessels, silos, storage bins, hoppers, vaults, and pits are spaces that may have limited means of entry.); and,

(3) Is not designed for continuous employee occupancy.

Be mindful that all three of these criteria must be in place to meet the OSHA definition of a confined space.  Also, keep in mind that whether or not a hazard is present inside the space is not relevant at this point. You are only trying to determine whether or not you have a confined space at your work site.

That being said, don’t buy into the false assumption that entry into a confined space begins only after a person gets their entire body inside of the space, because that is not the case. The OSHA definition of “entry” states that entry is considered to have occurred as soon as any part of the entrant’s body breaks the plane of an opening into the confined space. So, if your space meets the definition of a confined space that can be bodily entered (which means the employee being able to fit their entire body into the space), entry into that confined space is considered to have occurred as soon as any part of their body crosses any plane of entry into that space. Conversely, if the space cannot be bodily entered, then it is not a confined space, regardless of whether or not a worker is able to stick some part of their body into the space.

One final word of caution regarding this topic; don’t think that just because a space cannot be bodily entered and is therefore not covered by the confined space entry standards, that it is exempt from all other OSHA safety or health regulations. For example, we now know that a tank with an entry portal that is too small for a person to bodily enter is not a confined space. However, if the portal is still large enough for a person to stick their head inside, and the tank contains a deadly atmosphere, they could be seriously injured, or perhaps even die; they just wouldn’t have died inside of a confined space. In the case of this particular tank, there are other OSHA regulations pertaining to respiratory protection that would apply to protect the worker who sticks their head inside the tank; those rules just wouldn’t be part of the OSHA confined space entry standards.

OSHA Definition: “Limited or Restricted Means for Entry or Exit”

The second criteria listed in OSHA’s definition of a confined space is that the space has limited or restricted means for entry or exit. There is no definition for this term in the OSHA 1910 permit-required confined space entry standard. Therefore, many people believe the term means that there is only one way in and out of the space. But that is not correct; a confined space may have one entry point, or it may have a dozen.

The OSHA confined space advisor clarifies OSHA’s intent by explaining that a limited or restricted means for entry or exit exist where the occupant must crawl, climb, twist, be constrained in a narrow opening, follow a lengthy path, or otherwise exert unusual effort to enter or leave, or where the entrance may become sealed or secured against opening from inside. Also, the newer 1926 confined spaces in construction standard does include a definition for the term “limited or restricted means of entry or exit” in 1926.1202. That definition states it means “a condition that has a potential to impede an employee’s movement into or out of a confined space”. The definition goes on to explain that examples of a limited means of entry or exit include, but are not limited to, trip hazards, poor illumination, slippery floors, inclining surfaces, and ladders, all conditions which could make it difficult to escape the space should an emergency arise.

Based on the previous information, here is a non-exhaustive list of examples of conditions where a limited or restricted means for entry or exit could exist:

• Portals where the entrant must squeeze through to enter or exit the space horizontally, as well as where entry is made vertically;
• Hatches of a size or location requiring the entrant to climb or squeeze through;
• Manholes that the entrant must pass through an opening to get into or out of the space;
• A pipeline of a size that requires the worker to crawl to get through the pipe;
• Spaces such as open top pits or attics where the worker must climb up or down on a ladder to enter or exit the space;
• Spiral staircases, which can be difficult to climb or descend, which are used to access a space;
• Steep stairways, such as ships ladders and other non-standard stairways, used to access a space;
• Tight crawlspaces, such as beneath equipment, under floors, between walls, and above some ceilings; and;
• An underground utility tunnel where the worker must travel a long distance to get to the nearest exit point.

Is a Door Considered a Limited Means of Entry or Exit?

The question often arises as to whether or not OSHA considers a standard size doorway to be a limited or restricted means of entry or exit. This topic is not specifically addressed in the OSHA 1910 permit required confined space entry standard.  However, In the preamble to the 1910 general industry permit-required confined space standard, OSHA states that “doorways and other portals through which a person can walk are not to be considered a limited means of entry or exit.” However, the preamble goes on to explain that a space containing such a door or portal may still be deemed a confined space if an entrant’s ability to escape from inside the space in an emergency would be hindered.

OSHA further clarifies their position about doorways in a later amendment to the 1910 standard published in the Federal Register, where they state that “even if the door or portal of a space is of sufficient size, obstructions could make entry into or exit from the space difficult. The Agency intended that spaces which otherwise meet the definition of confined spaces, and which have obstructed entry or exits even though the portal is a standard size doorway, be classified as confined spaces.” In other words, a space with a standard doorway (which is a doorway at least two feet wide and at least six and one-half feet in height, according to OSHA’s FAQs page for their confined spaces in construction standard) would be considered to have a limited means of entry or exit if, inside that space, there are pipes, duct work, equipment, or other obstructions or obstacles that would make it difficult for a worker to access the door to escape in the case of an emergency, or if the door could lock and trap the person inside the space.

One more thing to keep in mind at some manufacturing and construction environments is that a large structure being constructed may not have a limited means of entry or exit – at least not initially.

But it may become a confined space with a limited means of entry or exit at a later point during the fabrication or construction process.  For example, an employee can easily walk into and out of a large diameter, horizontally-oriented steel vessel being fabricated if one or both ends are wide open, because no restricted entry or exit exists at that particular point in time. However, once the ends of the vessel are installed and employees must enter and exit the vessel through a portal or similar small opening, a limited means of entry and exit would then exist.

Third Criteria for the OSHA Definition of a Confined Space: Not Designed for Continuous Employee Occupancy

 The third and final criteria listed in OSHA’s definition of a confined space is that the space is not designed for continuous employee occupancy. For example, most underground utility vaults are not designed and outfitted with any safeguards to control a potentially hazardous atmosphere, nor are most underground vaults outfitted with an adequate light source. So, at a minimum, workers would most likely have to utilize a portable blower, auxiliary lighting, and a portable gas detector to safely enter and work inside such vaults.

 On the other hand, there are some underground utility vaults that has been engineered and constructed with a built-in ventilation system, lighting system, and gas detection system to maintain a safe atmosphere. Because such a vault has been designed by engineers for employees to enter and work without the need to implement any safeguards during the duration of their time inside the space, this particular utility vault would not meet this third criteria of the OSHA definition of a confined space, and therefore would not be considered a confined space.

Recap of the Three Criteria of the OSHA Confined Space Definition

 So, in review, here is a recap of the three criteria listed in OSHA’s definition of a confined space:

 Number 1 – the space is large enough and so configured that an employee can bodily enter and perform assigned work (that means the worker can get their entire body inside of the space);

Number 2 – the space has limited or restricted means for entry or exit (that means it would be hard to get into or out of in case of an emergency); and,

Number 3 – the space has not been designed for continuous employee occupancy.

 As a reminder, all three of the criteria listed above must be present for the space to meet the OSHA definition of a confined space. Also, remember that all confined spaces are not necessarily permit-required confined spaces; that is to be determined later.

In our next blog post (#7), we will provide numerous examples of confined spaces, including a few that you might not have thought about. Then, beginning with post #8, we will take a very deep dive into how to determine whether or not the spaces meeting OSHA’s definition of a confined space are to be subsequently classified as permit-required confined spaces, or non-permit confined spaces.

 Final Note: Do you find our confined space entry training blog to be helpful? If so, please send a link to our blog to others in your network who could benefit from this kind of information. Thanks, Curtis

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