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CONFINED SPACES Redefining the Safety Hierarchy in a Confined Space What are the steps you should first consider to ensure your confined space entries are safe and that workers are best equipped to respond if they are met with a life-threatening hazard? BY DAN LEMON Alot can happen in four minutes, especially when those four minutes are spent in a confined space. Confined spaces are prone to oxygen displacement, and after just four minutes without oxygen, you can experience brain damage or even die. It should be no surprise, then, that confined spaces are the leading cause of multiple fatalities in the workplace. That’s why it’s so important to take extra precautions to ensure safety in confined spaces. It’s an age-old horror story: a worker enters a confined space, most likely for routine maintenance or repair, and an atmospheric hazard is present. When the entrant doesn’t respond to the hole watch, their supervisor and peers get worried, so one of them enters the confined space to check on the original entrant only to be overcome by the same gas hazard. Unfortunately, this scenario is too common—The National Institute for Occupational Safety and Health (NIOSH) reports that 60 percent of confined space deaths are among these “would-be” rescuers who enter a confined space without understanding the hazards within. PARADORN KOTAN/Shutterstock.com When workers in confined spaces need your help, you can’t act on impulse – you need to be prepared with a plan and proper equipment in place long before the first worker enters a confined space. When creating a confined space entry plan, however, you need to think bigger than what the “traditional” hazards are to isolate. While most would say eliminating the hazard completely should be the first step in your safety hierarchy, it’s impossible to completely eradicate every potential hazard workers face. Below are the steps you should first consider putting in place to ensure your confined space entries are safe and that workers are best equipped to respond if they are met with a life- threatening hazard. Potential Risks in a Confined Space Because you can’t eliminate every potential hazard, you should first consider your overall approach to confined space entries. Before workers enter a confined space, you must complete a risk assessment (examining the environment in/around the confined space for entry location and size, energy or chemical sources, and lockout points), hazard assessment (examining what hazards workers could be exposed to), identify the personal protective equipment workers will need, and select properly trained workers to perform the job. After you’ve checked and prepared your equipment, you should sample the atmosphere from a safe location. Once you’ve safely approached the confined space and you’ve begun taking samples, you need to take things like stratification of gases into consideration. Gases settle in a space based on their weight in relation to air. Toxic gases that you would commonly encounter in confined spaces have a typical stratification pattern. For example, hydrogen sulfide (H2S) settles at the bottom—it’s a heavier- than-air gas. Carbone monoxide (CO), which is slightly lighter than air, tends to settle in the middle, while methane sits on top. However, these are not absolute rules. You also need to take into consideration things like air current or ventilation. You may find H2S at a different level due to these factors and when you see those readings on your gas detector, that doesn’t mean that your instrument is incorrect. It is likely detecting that gas at a different level. Remember, these are general guidelines, and for more specific information concerning confined space entry, consult your regulatory agencies for details. That said, no two confined spaces are the same. But they all have the potential to harm workers if you don’t identify, monitor, and control the dangers within, which means you need to ensure that your people – both full-time employees and contractors – have the right equipment to get the job done. Communication Amidst theInabilitytoCommunicate Once you’re aware of the risks within each confined space, supervisors need to ensure that workers (including contractors) understand the hazards of the space and that they have the safety and 24 Occupational Health & Safety | JULY/AUGUST 2023 www.ohsonline.com