Risks of working in confined spaces

Employees in many roles may face challenging and difficult environments in the workplace, but when these situations verge on dangerous, regulatory authorities must get involved to ensure workplace safety and employee well-being. 

Industrial facilities often have confined spaces, which workers are expected to navigate to complete their job, such as in engineering, electricity, cleaning, and manufacturing sectors. 

This article outlines the legislation and safety measures in place around the world to regulate confined spaces at work and prioritize worker health and safety. We also share some best practices and strategies companies can adopt to cover the risk and ensure worldwide compliance.

What are confined spaces?

The Health and Safety Executive (HSE) defines a confined space as ‘one which is both enclosed or largely enclosed and has a reasonably foreseeable specified risk…’.  

Examples of confined spaces often encountered in the workplace include: 

• Manholes such as sewer holes, underground pipes, and tunnels 

• Storage tanks containing liquids and gases, which can be located above or below ground level 

• Excavations  

• Trenches  

• Reactors 

• Turbines 

• Ducts 

• Crawl spaces 

• Wells 

• Tanks 

It’s helpful to know that the definition of a confined space at work can vary from one country, or region, to another, with associated legislation affected by the definition. 

For example, in the United Kingdom, Ireland, and Germany, confined spaces are often defined broadly, with a focus on an ‘enclosed’ space and ‘foreseeable specified risks’ as defined by the HSE. 

Contrastingly, Japan and South Korea have adopted definition focusing on the risk of oxygen-deficiency within the confined space. In this region, work carried out in “oxygen deficiency-danger places” are referred to as “oxygen depletive operations”. Further, in China, an enclosed space is defined by being ‘closed, narrow, and poorly ventilated’.
 

What are the risks of working in confined spaces? 

Confined spaces carry many risks for workers, namely due to the inability to quickly escape. The risk of being trapped is followed by a number of hazards, such as fires and explosions, loss of consciousness from poor air ventilation and circulation, asphyxiation from lack of oxygen, and drowning, to name a few.  

Fatalities in confined spaces can occur quickly. In an atmosphere that contains no oxygen, consciousness is lost in a matter of seconds. When an oxygen-free atmosphere is breathed, the body reverses the breathing process and instead of carbon dioxide, oxygen is diffused from the blood in the lungs. 

According to the HSE, around 15 UK workers lose their lives due to the risks of confined spaces each year. In the United States, the US Bureau of Labor Statistics recorded 1,030 deaths from occupational injuries involving a confined space between 2011 – 2018. 

Safety protocols are therefore paramount to worker protection.

Business approaches to monitoring the hazards of confined spaces

If businesses cannot avoid their workers having to undertake tasks in confined spaces, they must instead properly conduct safety assessments to uncover the risks and identify strategies to keep their employees safe. 

Determining risk exposure demands the management of environment, health and safety (EHS) issues at the corporate level, ensuring that corporate procedures set high standards. Leveraging risk assessment processes to identify confined space hazards before work begins is crucial. 

Some examples may include: 

• Ensuring proper ventilation, or the removal of potentially harmful fumes and hazardous substances from confined spaces 

• Identifying how to close off areas where liquids or gases could seep in to the enclosed space 

• Applying the best personal protective equipment (PPE) such as a breathing apparatus, protective clothing, or suitable footwear 

• Assessing the safety and accessibility of the confined space entry and exit 

Knowing the potential hazards and hidden dangers of confined spaces is the first step to ensuring occupational health and safety.

Regulations on confined spaces

As aforementioned, different countries around the world hold varying definitions of what a confined space is, which can be reflected in their legislation.
 

UK — The Confined Spaces Regulations 1997 

This UK regulation came into force on 28 January 1998 to govern the health and safety of workers in enclosed spaces. 

The Confined Spaces Regulations 1997 defines a confined space as ‘any place, including any chamber, tank, vat, silo, pit, trench, pipe, sewer, flue, well or other similar space in which, by virtue of its enclosed nature, there arises a reasonably foreseeable specified risk’. 

The Regulation refers to the following hazards: fires and explosions; loss of consciousness from increased body temperature; loss of consciousness or asphyxiation from gas, fumes, vapors, or lack of oxygen; drowning from increasing levels of liquid; asphyxiation from an inability to reach a respirable environment due to free-flowing solid. 

UK employers subject to the 1997 Regulations are expected to conduct risk assessments, ensure workers undertake adequate training for working in confined spaces, supply supervision, and establish and implement emergency procedures in case of incidents.
 

US — Permit-required confined spaces 

In the United States, the Occupational Safety and Health Administration (OSHA) enforced regulations to protect workers from the hazards of enclosed spaces, outlined in the ‘Permit-required confined spaces’ standards. 

OSHA defines a confined space as being ‘large enough and so configured that an employee can bodily enter and perform assigned work; and has limited or restricted means for entry or exit… and is not designed for continuous employee occupancy.’ 

The standard covers several significant key areas of confined space work: 

• Identifying confined spaces in the workplace 

• Implementing a permit-required program 

• Organizing training for employees 

• Assessing procedures for entry, rescue, and emergency response 

• Enforcement and penalties for violations of these standards 

For permit-required confined spaces, OSHA mandates that employees identify, analyze, and implement: 

• Safety measures for pre-entry to the confined space 

• Testing and monitoring of the atmosphere to ensure the space is safe 

• Safety measures for ventilation 

• Emergency procedures and rescue response plans
   

China — Provisions on the Safety of Operations in Confined Spaces of Industry and Trade Enterprises 

In the Asia-Pacific region, China’s Ministry of Emergency Management announced their revised safety regulations for confined spaces in industry and trade enterprises in December 2023, which came into effect in January 2024. 

The Provisions outlines methods of supervising and managing workplace safety, including emergency response plans, safety responsibilities for confined space operations, supervision of operations, and associated penalties.
 

Workplace safety in Europe 

While the European Union (EU) hasn’t yet introduced any specific legislation relating to work in confined spaces, the Framework Council Directive 89/391/EEC of 12 June 1989 covers all aspects of health and safety in the workplace, mandating a duty on employers to consider the characteristics of their facilities — including confined spaces. 

Annex IV to Council Directive 92/57/EEC of 24 June 1992 on safety and health requirements at temporary or mobile construction sites include specific requirements regarding confined spaces. 

Further, Annex IV specifies that if necessary: 

• A confined atmosphere must be monitored and appropriate steps taken to prevent workplace hazards 

• Workers may not be exposed to a high-risk confined atmosphere under any circumstances 

• Workers must be watched at all times from the outside, with all appropriate precautions taken to ensure effective and immediate assistance

Managing risks of working in confined spaces

The best approach for companies where workers are involved in confined space activities involved identifying the risks associated with the environment, including any atmospheric risks, unfavorable conditions, the presence or emergence of harmful substances or harmful materials, and any other potential hazards from the work being carried out. 

A risk analysis will help organizations determine, on a case-by-case basis, which confined spaces within their facility require control and supervision. All risk assessments need to consider the various definitions of confined spaces, the health hazards, and the risk exposure. 

Maintaining workplace safety is not only a prerequisite to compliance; it’s also the right thing to do.