A confined space is an area with limited or restricted means of entry or exit, is large enough for an employee to enter and perform assigned work, and is not designed for continuous occupancy. Confined spaces are found in many workplaces. Such spaces may include, but are not limited to, underground vaults, tanks, storage bins, pits, dikes, vessels, silos and elevator shafts.
In addition, when a confined space has ANY of the following characteristics, it is considered a permit-required confined space (PRCS):
- It contains or has the potential to contain a hazardous atmosphere.
- It contains a material that has the potential for engulfing an entrant.
- It has an internal configuration that might cause an entrant to be trapped or asphyxiated by inwardly converging walls or by a floor that slopes downward and tapers to a smaller cross section.
- It contains any other recognized serious safety or health hazards.
Many workplaces contain spaces that are considered to be “confined” because their configurations hinder the activities of any employees who must enter into, work in and exit from them. In many instances, employees who work in confined spaces also face increased risk of exposure to serious physical injury.
What are the hazards associated with a confined space?
Confinement, limited access and restricted airflow can result in hazardous conditions that would not normally arise in an open workplace. Increased risk of exposure to serious physical injury from entrapment, engulfment and hazardous atmospheric conditions can result.
What can I do to protect myself?
Make sure you know all of the appropriate procedures and precautions to take for entry into and exit from confined spaces. If there are hazardous confined spaces where you work, your employer is required to have a permit-required confined space program, permit system, emergency procedures, appropriate engineering and work practice controls and to provide you with training and appropriate personal protective equipment.
What resources are available to assist employers?
Safety and Health Programs
This example confined space entry program can be downloaded and customized to fit an individual workplace. The program is based on information found in the general industry standards, 29 CFR 1910.146. Also these example programs may also be applicable for workplaces with confined space hazards: hazard communication program; personal protective equipment hazard assessment; and respiratory protection program.
Training and Outreach Services
Presentations on confined spaces are available for workplaces in general industry and construction and can assist employers in training their staff. The presentations should be modified to address site-specific conditions and hazards. In addition, these presentations on personal protective equipment, respiratory protection, and hazard communication can be useful in providing training to your employees. Also available are pre-recorded webinars on confined spaces in general industry and confined spaces in construction which can be accessed at any time.
Lastly, the NCDOL Library offers free safety and health videos (including streaming video services) and related research assistance on consensus standards (i.e., ANSI, NFPA, NEC).
A-Z Safety and Health Topics
The consultative services bureau provides free and confidential onsite consultation regarding worksite safety and health hazards.
Which standards apply?
OSH has adopted the following standards which are applicable to confined spaces in North Carolina. Note: Please also check the standards information and activity webpage to see if there has been any recent or upcoming regulatory activity on this topic.
- 29 CFR 1910.146 – confined spaces
Maritime, Shipyard Employment
- 29 CFR 1915, Subpart B – confined and enclosed spaces and other dangerous atmospheres in shipyard employment
Maritime, Marine Terminals
- 29 CFR 1917.23–25 – hazardous atmospheres and substances
- 29 CFR 1926, Subpart AA – confined spaces in construction
In addition, in 29 CFR 1910, Subpart R - Special Industries, several of the industry-specific standards also address confined or enclosed spaces:
- 29 CFR 1910.261 – pulp, paper and paperboard mills
- 29 CFR 1910.268 – telecommunications
- 29 CFR 1910.272 – grain handling facilities
Other standards that may apply include:
- 29 CFR 1910.124 – general requirements for dipping and coating operations
- 29 CFR 1910.252 – general requirements, welding, cutting and brazing
Other Applicable Standards
The Which OSHA Standards Apply webpage can also help identify other standards that may be applicable to your worksite.
Where can I learn more?
- Industry Guide 48 - OSHA Construction Industry Standards Requiring Programs, Inspections, Procedures, Records and/or Training provides requirements for standards related to confined spaces in construction.
- Industry Guide 49 - OSHA General Industry Standards Requiring Programs, Inspections, Procedures, Records and/or Training provides requirements for standards related to confined spaces in general industry.
- Industry Guide 53 - OSHA Shipyard Employment Standards Requiring Programs, Inspections, Procedures, Records and/or Training highlights the requirements of standards related to confined spaces in shipyard employment.
- Industry Guide 54 - OSHA Marine Terminal Standards Requiring Programs, Inspections, Procedures, Records and/or Training highlights the requirements of standards related to confined spaces at marine terminals.
- NCDOL Investigates: Confined Space Accident provides an overview of the investigation process used for confined space accidents.
- Compliance Directive: CPL 02-00-100 Application of the Permit-Required Confined Spaces Standard, 29 CFR 1910.146 establishes enforcement policy and provides explanation of the standard to ensure uniform enforcement.
- Standards Notice: SN 67 - pplicability of the Permit Required Confined Space Standard, 29 CFR 1910.146, to Concrete Mixing Trucks, provides the application of the permit required standard to concrete mixing trucks.
- Standards Notice: SN 54 - Standby Personnel at Telecommunications Manhole provides guidance for Compliance Safety and Health Officers to determine when standby personnel are required to be present when employees are performing telecommunications work.
If you would like to receive interpretive guidance on this or any other OSH standard or topic, you can submit your questions using the Ask OSH web form, by e-mail to email@example.com or by calling 919-707-7876.