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Entering and Working in Confined Spaces

Confined Space Entry
Contents of Manual

Section 1
  ID Confined Space

Section 2
Section 3
Section 4
List of Terms

As updated by OSU Environmental Health & Safety April, 2004

1.  Identifying Confined Spaces


Identifying Confined Spaces

Identifying Confined Space Hazards

Confined Space Entry Program

Responsibilities and Training Requirements

Confined Space Permit

Recognition is an important aspect of making a safe entry into a confined space. Not all confined spaces will be considered permit-required confined spaces and being able to identify the difference between the two is important. To clarify what constitutes a Confined Space, the following definition will be used.

A Confined Space is any space that has the following characteristics:

  1. It is large enough or so configured that an employee can bodily enter and perform assigned work.

  2. It has limited or restricted means for entry or exit.
    Confined-space openings are limited primarily by size and location. Openings may be small in size and may be difficult to move through easily. However, in some cases openings may be very large; for example, open-topped spaces such as pits or excavations. Entrance and exit may be required from top, bottom, or side. In some cases, having to access the work area by a fixed ladder may constitute limited or restricted entry or exit. Size or location will generally make rescue efforts difficult.

  3. It is not designed for continuous employee occupancy.
    Most confined spaces are not designed for employees to enter and work on a routine basis. They may be designed to store a product, enclose materials and processes, or transport products or substances. Because they are not designed for continuous occupancy, frequently they will not have good ventilation or lighting. Therefore, occasional employee entry for inspection, maintenance, repair, cleanup, or similar tasks, can be difficult and dangerous. The danger associated with entry may come from chemical or physical hazards within the space.

Contents of Manual
ID Confined Space
Permit Form (html)
Permit Form (pdf)

A Non-Permit Confined Space is a confined space that does not contain, nor has the potential to contain, any hazard capable of causing death or serious physical harm. Examples of non-permit required confined spaces might include the interiors of HVAC units, certain air plenums and pipe chases, attics, walk-in freezers or refrigerators, and some building crawl spaces.

A Permit-Required Confined Space is a confined space that is potentially hazardous. A permit-required confined space has one or more of the following characteristics:

  1. Contains or has a 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 that slopes downward and tapers to a smaller cross-section; or

  4. Contains any other recognized serious safety or health hazard. Examples of serious safety or health hazards might include:

    • Fall hazards
    • Unguarded machinery
    • Extreme heat or cold
    • Steam pipes or chemical lines
    • Hazardous noise levels
    • Electrical hazards
    • Presence of asbestos
    • Potentially hazardous levels of dust (such as might occur at the Feed Mill)

Because of the lack of ventilation in most confined spaces, they will have the potential for a hazardous atmosphere. Therefore, they must be designated "permit-required," and the procedures for making entry into a permit-required space must be followed. Examples of permit-required confined spaces at OSU include sewers, electrical vaults, steam tunnels, sump pits, certain mechanical rooms, some excavations, and other types of enclosures.

Any space that is accessed by lifting a manhole cover shall be considered a permit-required confined space. Additionally, some roofs, the Lake Carl Blackwell dam access tunnel, certain grain storage facilities, and equipment access areas may be designated permit-required confined spaces even though they don't technically meet the definition (i.e., they may not really have limited or restricted means of entry or exit). These areas shall be clearly marked as permit-required spaces.

OSU has two blanket designations concerning permit-required confined spaces:

  • Steam tunnels, regardless of access, shall be considered permit-required confined spaces (i.e., as soon as you step into a steam tunnel, you are in a permit-required confined space, even if you walked into it through a mechanical room).
  • Attics are not considered to be permit-required confined spaces.

Supervisors are directly responsible for ensuring the safety of their employees in regards to confined spaces. It is their responsibility to evaluate potentially hazardous spaces within their facilities and areas to ensure that the proper precautions are taken for safety. This includes clearly marking permit-required confined spaces, training employees, and ensuring proper entry procedures are followed. These responsibilities may be delegated to another competent person provided he/she is qualified.

Physical Plant supervisors are responsible for ensuring their employees are properly trained to do the jobs they are sent to do. This includes recognition of confined spaces and proper procedures for making entry into permit-required confined spaces whenever necessary.   No Physical Plant employee shall be sent on a job that potentially involves work in a confined space unless they have been properly trained in confined space entry procedures.

It may be determined that a confined space presents no real danger for employees. However, it is recommended that all spaces be considered potentially dangerous until they have been evaluated and tested. Once a space has been evaluated, the Environmental Health and Safety Department shall determine if the confined space requires a permit and will apply appropriate labeling.


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