Confined spaces have long posed a physical and environmental risk to industrial workers. But what are “confined spaces” exactly? What are the risks associated with working in them? And what can you do to ensure your team stays safe?
What Is a Confined Space?
Most of us associate the term “confined space” with tunnels and crawl spaces, but the definition is considerably broader. Basically, a confined space is an area that isn’t designed for people *but* is large enough for workers to enter and perform certain jobs.
The Occupational Safety and Health Administration (OSHA) defines a confined space as an area that “has limited or restricted means for entry or exit and is not designed for continuous occupancy. Confined spaces include, but are not limited to, tanks, vessels, silos, storage bins, hoppers, vaults, pits, manholes, tunnels, equipment housings, ductwork, pipelines, etc.”
The Hazards of Confined Space Work: 129 Deaths per Year
According to a fact sheet issued by the U.S. Department of Labor in 2020, 129 workers (on average) die each year from occupational injuries involving a confined space. There are four primary dangers associated with confined space work, which are naturally exacerbated by a lack of accessibility that makes exiting difficult: asphyxiation, flooding, fires/explosions, and heat stress.
Asphyxiation
Since many confined spaces lack proper ventilation, they are susceptible to a buildup of gases and fumes. These may be the result of a leak, a byproduct of the work being carried out (e.g. welding, adhesives, paint fumes), or simply a natural occurrence.
In some cases, it may simply be a lack of oxygen that poses the danger. Without proper ventilation, workers may quickly use up a limited oxygen supply without realizing it. In addition, some naturally occurring chemical reactions between oxygen and soils, groundwater, chalk, or limestone can produce carbon dioxide (which displaces oxygen). Even rust forming inside the confined space can result in a lack of oxygen.
Flooding
Confined spaces, especially those involved in drainage or sewer work, may be prone to flooding. In a small space especially, water or other liquid can quickly fill the area (sometimes in a matter of seconds), trapping and potentially drowning any workers caught within.
Fires/Explosions
Flammable vapors, liquids, gases, dust, or even an excess of oxygen within a confined space can increase the risk of fire and/or explosions. Of course, this risk is compounded by any hot work (e.g. electric/gas welding, cutting, brazing, or similar flame or spark-producing operations).
Heat Stress
Heat stress is a dangerous condition that occurs when your body heats up faster than it can cool itself down, often resulting in heatstroke, exhaustion, and collapse. Heat can rise rapidly in a confined space due to its enclosed nature, especially with the presence of hot equipment. This can be especially problematic (and potentially fatal) when combined with the lack of access as it makes escape (or potential rescue) even more difficult.
Other Confined Space Dangers
This list is not comprehensive by any means. Other potential confined space hazards include angled walls or sloping floors that could potentially trap workers, unstable/collapsing surfaces, open machinery, exposed live wires, etc.
Working Safely in Confined Spaces
Each confined space comes with its own set of potential hazards; there are no one-size-fits-all approaches to confined space safety. That said, there are some steps you can take to mitigate the dangers, reduce the risks, and maintain the safety of your team.
- Perform a thorough hazard assessment for each confined space to ensure all workers are aware of the risks at hand.
- Provide verbal and written protocols to identify entry/exit barriers, specific rescue procedures, monitoring efforts, and information regarding the personal protective equipment.
- Conduct regular assessments of confined spaces to make sure the ventilation systems are working properly and that there has been no build-up of poisonous gases, flammable vapors, etc.
- Implement a monitoring system that ensures your workers (and their environment) are safe and gives you a heads up on potential problems before they occur.