Getting trapped in a confined space carries multiple risks that can leave a lasting impact. Even without physical injuries, confined spaces can harm your mental health, leaving you to deal with the consequences for years. If you ever find yourself trapped, the sooner someone rescues you, the better. Unfortunately, this isn’t always straightforward. You might often be unaware you’re in a confined space. This article defines what a confined space is and provides confined space examples to help you identify and act quickly if you ever find yourself in one.
What Is a Confined Space?
We define a confined space as an enclosed space that is hard to access. A confined space can exist below or above ground. Despite its name, a confined space isn’t necessarily entirely enclosed. It might only be partly enclosed, or enclosed to an extent that increases the risk of you getting stuck inside.
In practical terms, a confined space can be any place – such as a chamber, tank, vat, silo, pit, trench, pipe, sewer, flue, well, or other similar area – where, due to its enclosed nature, there is a reasonably foreseeable risk to your safety. The specific dangers may vary, but are closely tied to the environment and structure of the space itself.
Most confined spaces pose risks for these reasons:
- Restricted access: Entering or exiting these spaces is difficult.
- Communication challenges: Individuals outside may struggle to determine what’s happening or see those inside.
- Ventilation issues: You might find it difficult to breathe and eventually run out of fresh oxygen, which can seriously compromise your health.
- Flooding risk: If a leak or other incident forces water inside, these spaces can fill quickly, thereby increasing your risk of drowning.
These characteristics – combined with the unpredictable hazards that can develop inside – mean confined spaces are inherently dangerous, making awareness and caution essential whenever you encounter one. These factors also make it difficult to escape a confined space. Given these risks, you also need a qualified professional to rescue you.
Most people aren’t supposed to occupy these spaces. However, maintenance and repair teams may need to access them to clean, renovate, or repair damage. Companies commonly use a confined space permit to work when accessing these spaces. However, given the dangers, the work can still be hazardous, and a rescue team should be on standby to address any issues that may arise.
What Is a Non-Permit-Required Confined Space?
Not every confined space falls under the same level of risk. In fact, OSHA makes an important distinction between permit-required and non-permit-required confined spaces.
A non-permit-required confined space is an enclosed or partially enclosed area that meets the standard definition of a confined space – such as limited entry or exit and challenging ventilation – but doesn’t contain any known serious hazards. Think of places like small storage rooms, residential attics, or shallow crawl spaces. These spots may be tricky to get in and out of, but they don’t typically have dangers like toxic gases, engulfment risks, or dangerous machinery operating inside.
Even though these locations aren’t as immediately threatening as their permit-required counterparts, workers still need to take precautions. Wearing proper personal protective equipment (PPE), notifying others of your location, and maintaining clear communication are essential steps. That way, if a situation does arise, help can be sent your way without delay.
Confined Elevated Spaces
Confined elevated spaces are any areas located above ground level that restrict your movement and access. Common examples include rooftops, water towers, attic crawl spaces, and raised maintenance platforms – places you can only reach by climbing a ladder, stairs, or using a lift.
These spaces present a unique set of hazards, combining the risks of a confined environment with the dangers associated with working at heights. If you’re required to enter an elevated confined space, watch out for:
- Difficult or limited entry and exit points, making evacuation in an emergency challenging
- Restricted ventilation, which can lead to air quality issues just like in below-ground spaces
- Fall hazards, since slips or trips can result in serious injury from greater heights
- Complicated rescue operations, as reaching someone in trouble in these elevated spots, often require special equipment and trained personnel
Because the consequences can be severe – think both falling and suffocating at the same time – strict safety protocols, like fall protection harnesses and regular communication checks, are a must every time work is carried out in these spaces.
Mechanical Spaces
Mechanical spaces are rooms or enclosures where you’ll find equipment such as HVAC units, boilers, turbines, and various other building systems packed in – think of the crammed, humming corners of office buildings and industrial sites everywhere from New York to Mumbai. These spaces often tick all the boxes for a confined space: they’re typically difficult to access, not designed for regular occupancy, and can pose serious health and safety risks.
The primary hazards here stem from both the equipment itself and the surrounding environment. Poor ventilation, limited entry points, and the presence of machinery make these spaces especially treacherous during maintenance or repairs. In some cases, mechanical spaces are classified as “permit-required” confined spaces, meaning extra precautions and paperwork are necessary before anyone enters. To stay safe, workers must follow strict protocols, such as locking out and tagging any equipment that could accidentally start up, and ensuring a clear plan is in place for entering and exiting safely.
Just like other confined spaces, mechanical spaces demand careful preparation and should never be approached without a rescue plan in place.
Whether you’re updating a filter or undertaking a major overhaul, always plan the work, control the risks, and ensure everyone is on the same page before beginning. Good habits and solid documentation save lives – sometimes, it’s as simple as that.
20 Confined Space Examples To Keep an Eye On
As mentioned, you may not always know if something qualifies as a confined space. To help you, here are 20 confined space examples to remember:
1. Manholes
A manhole is typically an average-sized opening leading to a confined space. Also known as a utility hole, maintenance hole, or sewer hole, it serves as both an entry point and a confined space itself. Once you enter a manhole, you are in a confined space – there’s no two ways about it. Working in a manhole exposes you to potential dangers that can lead to serious accidents. Common examples include slips and falls, oxygen depletion, fire or explosion, gas poisoning, drowning, heat stress, and exposure to fumes, vapor, and gas, leading to asphyxiation.
Manholes are commonly found in city streets, industrial sites, and utility corridors, providing access to underground utilities such as sewers, electrical systems, and telecommunications lines. Because manholes are often cramped, poorly ventilated, and not designed for continuous occupancy, extra caution is essential. Even a routine inspection can turn hazardous in moments if proper procedures aren’t followed. Always ensure you have a rescue plan, test the atmosphere before entering, and use appropriate personal protective equipment—no matter how quick the job might seem.
2. Storage Tanks and Vats
A storage tank or vat container holds liquids and gases. Several hazards are associated with these types of confined spaces. Often, any potential hazards result from the materials stored inside the tank or container. These materials may be toxic, explosive, or flammable.
3. Sewers
Sewers are underground tunnel systems and pipes that carry waste matter, drainage water, and other hazardous substances that can pose health risks. Access is typically restricted, usually through a manhole, and these environments are fully enclosed – fitting the classic definition of a confined space. Due to the limited entry points and the presence of hazardous gases or potential flooding, sewers can quickly become life-threatening. Notably, several incidents have occurred where workers have faced severe risks, such as near-drownings and toxic exposure, highlighting the importance of strict safety procedures in these spaces.
4. Trenches
Trenches are above-ground confined space examples. You usually dig them for short-term work. However, they tend to be enclosed and have restricted access, posing several risks.
5. Excavations
Excavations provide temporary access to things below ground. Contractors may also make them for construction purposes. Excavations are often unstable and prone to collapsing or flooding.
6. Pits
Pits are hollow indentations in the ground. You can consider various types of pits. They are usually open at the surface, but extracting people from them can be difficult.
7. Lifts and Access Shafts
These confined spaces consist of a vertical shaft that can extend both above and below ground. They qualify as confined spaces due to limited access and difficulty exiting. They present a high risk of slips/falls and other injuries.
8. Tunnels
Getting trapped in a tunnel can pose various dangers, as you might find it difficult to find your way back to the surface. You also face the possibility of floods, cave-ins, and other dangers.
9. Pipes
Pipes are narrow conduits that transport gases and liquids from one area to another. They tend to run both horizontally and vertically.
10. Chambers
A chamber is a small room that can be partially or fully sealed and enclosed. Due to their limited access, they often serve as a confined space that is difficult to escape.
11. Ducts
Ducts, conduits, pipe systems, and passages are narrow spaces that transmit heat and air for ventilation, heating, and air conditioning.
12. Silos
A silo is a partially or fully enclosed structure that stores bulk materials. Common examples include grain, cement, sawdust, silage, etc.
13. Boilers
Boilers and boiler rooms are typically used in large-scale industrial applications. These confined spaces pose a variety of risks, and you must take precautions when venturing inside for maintenance and repair purposes.
14. Flues
A flue is a pipe, a duct, or an opening at the top of a chimney. It conveys exhaust gases released by a furnace, boiler, water heater, fireplace, or generator and releases them into the environment.
15. Vaults
A vault is an underground storage area that is enclosed to limit access. You can normally enter it using a maintenance hole.
16. Wells
A well is a type of vertical excavation created in the ground to access liquid resources. A water well is the most common example of this type of confined space.
17. Hoppers
A hopper is a large container shaped like a pyramid or a cone. Industries utilize it for holding particulate matter, such as gravel, dust, and seeds. It can also dispense these materials outward using a chute.
18. Vessels and Voids
These confined spaces typically serve as containers to hold something, or they may be completely empty areas that surround other structures. You may need to access them for maintenance and other work during the construction process.
19. Unventilated Rooms and Areas In a Building
These confined spaces tend to exist below ground level. However, you may also find them on upper floors. Poor ventilation can lead to a buildup of hazardous gases or a lack of oxygen, making these areas hazardous, even if they seem relatively accessible at first glance.
20. Cargo Holds Within Ships
The cargo hold is a part of a ship where goods are stored. They tend to be enclosed spaces and have a hatch at the top to restrict access. Even smaller boats can have confined spaces that require entry for maintenance or repairs – often increasing the risk to workers. For example, there have been serious incidents where employees working inside a yacht’s confined space were injured when flammable solvent fumes were ignited by power tools during paint removal. This underscores the importance of proper risk management and control measures whenever accessing ship cargo holds or similar enclosed spaces.
Are you planning to carry out maintenance or repair work in any of the confined space examples mentioned above? If so, contact DCS Rescue Services to have a reliable technical rescue team on standby and ensure the safety of your team. Contact us today to learn more!