Did you know OSHA estimates that more than 200,000 general industry establishments in the U.S. — employing around 12 million people — have confined spaces? Among those sites, approximately 1.6 million people enter confined spaces every year.

To review, a confined space is any space with limited means of entry or exit that is large enough for a person to enter to perform work but is not designed for continuous occupancy. Confined spaces include storage bins, sewers, tanks, silos, vaults, pits and many more locations that have cramped spaces and narrow openings. There are two basic categories of confined spaces: those that require a permit and are regulated by OSHA, and those that do not. Permit-required confined spaces fall under the OSHA standard 1910.146, which was developed to reduce fatalities in confined spaces.

Permit-required confined spaces under OSHA standard 1910.146 have one or more of the following dangers:
  • Contain or have the potential to contain a hazardous atmosphere 
  • Contain a material that has the ability to overcome an entrant
  • Contain an internal design where a worker could be trapped or asphyxiated by inwardly converging walls or by a floor that slopes downward and narrows to a smaller cross-section
  • Contain any other recognized serious safety hazard

Recognition is your first step

Recognition of a permit-required confined space is the first step in preventing fatalities. The next step is for the company to develop and implement a written safety program for all permit-required confined spaces that complies with OSHA 1910.146. The company is also responsible for employee training on confined space entry and providing proper personal protective or fall protection equipment. Even if the confined space is not regulated by OSHA, appropriate fall protection equipment and rescue procedures should be used in any confined space that presents a fall hazard.

Fall protection checklist

When selecting fall protection equipment for confined spaces, keep in mind the “ABCs” of fall protection: an anchorage, body support and a connector.

A – Anchorage There are many anchorage options, starting with a tripod. Tripods are easy to transport and set up, but they don’t fit all opening sizes. That’s where a davit arm or davit post comes in handy because they have many different base configurations. Davit systems are available in either fixed position bases or portable bases. Further, a counterweight system can be employed when access to a confined space prohibits the use of a tripod or davit arm. This system uses counterweights to balance the load of a person being lowered. Finally, if the job site requires entering a confined space horizontally rather than vertically, a side-entry system is needed. This system clamps onto the access point to allow an anchorage and base for attaching a winch device.

B - Body Support Specialized harnesses have D-rings on the top of both shoulder straps and a device called a Y-lanyard to connect the two D-rings to a winch line. This enables the worker to be raised or lowered in a fully vertical position. Comfort and durability are major factors if an employee will be working in the confined space for a long period of time. Economical, more basic harnesses are available as well for employees who rarely need to access the confined space or who need access for short periods of time.

C – Connector Consider the connector, often a winch connected to the tripod or davit system that allows the attendant to raise and lower the entrant. Always use mechanical devices that are rated for personnel use (not just materials) and incorporate fail-safe back-up braking systems in case the winch operator loses control of the crank. Some winches have a power drive option allowing automatic or manual operation, very beneficial when raising/lowering for long periods of time.

Rescue & retrieval

“What is the appropriate rescue plan for confined spaces?” Here are three categories of confined space rescue: Self-rescue: The individual exits the space on his or her own. This is the preferred rescue method whenever possible.

Non-entry rescue: The rescuer removes the worker without having anyone else enter the confined space. For example, this can be done using a winch line attached to the person in the confined space. Entry rescue: If self-rescue and non-entry rescue are impossible, a trained worker(s) will enter the confined space to rescue the trapped person.

Awareness is key

When a worker senses danger in a confined space, he should remove himself from the space immediately whenever possible. Self-rescue is always the safest and fastest option. Entry rescue should be the last resort — to reiterate, confined space deaths happen often during rescue situations. Entry rescue workers must remember to use proper confined space and fall protection equipment, like a full-body harness connected to a winch and davit system. If the rescue entrant worker is fully connected and becomes incapacitated, a non-entry rescue can be performed by raising him up remotely from above.

Proper rescue training is a must. Confined space rescue training involves both classroom and hands-on training, using exercises simulating the on-site confined space conditions in which the company is working. Some major fall protection manufacturers provide such training, either on or off-site. Usually, these courses will train workers to be attendants, entrants, supervisors and/or rescuers, and take a day to a few days to complete. Training includes recognition of hazards, control of hazards, use of monitoring equipment, use of personal protective equipment, use of rescue equipment, a plan for an annual practice of rescues and documentation of program completion.

Many confined space deaths are preventable. First, identify potential confined spaces on the job site. Second, put together a written safety plan as required by OSHA 1910.146. Third, make sure all workers are familiar with the plan, have proper equipment and know how to use it, and have undergone the appropriate training. Don’t become a statistic on an OSHA report.