Some people experience claustrophobia (a fear of enclosed spaces). Although this may sound absurd to most of us, it arises from a legitimate concern. All phobias stem from real dangers, and confined spaces are no exception. 

Confined spaces, such as tanks, pits, or chambers, may not appear threatening at first glance, but their enclosed nature can create conditions hazardous enough to require emergency intervention. 

Confined spaces, whether they contain harmful gases, flammable atmospheres, or a lack of oxygen, can pose severe risks to workers if they are not adequately assessed and managed.

According to the Canadian Standards Association, proper confined space risk assessment control measures can prevent 85% of incidents.

This blog will help you understand how to perform confined space risk assessment and why there is a need for confined space risk assessment and control measures. 

From identifying the confined space hazards to understanding why these spaces can be inherently dangerous, we will cover all the horizontal and vertical depths of the subject in this detailed guide. 

Let’s start by exploring what defines a confined space and why assessing its risks and hazards is a non-negotiable aspect of workplace safety.

What is Confined Space Risk Assessment?

Confined space risk assessment involves identifying, evaluating, and mitigating the hazards of working in confined spaces. These spaces (characterized by their enclosed nature) often pose unique risks, such as: 

1. Toxic atmospheres
2. Limited oxygen levels
3. Entrapment hazards

A thorough risk assessment identifies these hazards and determines their severity and likelihood. A detailed confined space hazard analysis helps develop effective safety protocols. 

The assessment sets the stage to ensure that confined spaces are approached with a clear understanding of the potential dangers and the resources needed to manage them.

The significance of confined space risk assessment lies in ensuring workplace safety to curb the likelihood of workplace injuries and fatalities. 

For instance, environments with the potential for oxygen deficiency require continuous atmospheric monitoring and the provision of self-contained breathing apparatus (SCBA) for workers. 

The process typically involves a structured approach using templates and safety checklists to ensure consistency and comprehensiveness. This systematic, foolproof workflow guides assessors in evaluating critical factors, such as:

1. The presence of hazardous materials
2. The need for specialized equipment
3. The challenges or obstacles in evacuation
4. The availability of emergency response plans

Confined space hazards risk assessment checklists provide a standardized way to document findings and verify all aspects of the confined space.

The depth of confined space risk assessment makes proper Confined Space Awareness Training crucial for employers, who must consider it to ensure appropriate employee training.

What Makes a Space Confined?

Remember the “The Hatch” from 2004’s famous series LOST? Imagine getting stuck in a hatch with no one to rescue you unless you are lucky enough to find “Dharma Initiatives” candies. This is what a confined space looks like. 

Confined spaces are defined by specific criteria that distinguish them from other work environments. Below are these crucial criteria you must know to identify and manage their associated risks.

1. Limited Openings for Entry and Exit

Confined spaces typically have restricted entry and exit points, making accessing or evacuating quickly in emergencies difficult. For example: 

1. Large containers with liquids or gases have narrow access hatches, challenging entry and exit.
2. Massive pits for storing bulk materials like cement, with limited openings at the top or bottom that restrict worker movement.
3. For bulk goods like grains, chemicals, or coal, containers often require workers to access them through small doors or hatches for maintenance or material handling.

These limited openings also restrict ventilation, further elevating the risk of hazardous atmospheres.

2. Sufficient Space for a Worker to Enter and Conduct Work

A confined space allows workers to enter and perform tasks physically, even though the area may be cramped. Such as:

1. Underground tunnels for transportation or utilities provide sufficient space for workers to install or repair infrastructure. But they pose risks of entrapment or low oxygen levels.
2. Boilers that generate steam or hot water for heating or power generation, with internal chambers large enough for workers to enter for inspections or repairs.
3. Pipelines carrying fluids or gases over vast distances also enable workers to enter for maintenance or to construct new pipelines.

Despite its small size, the space accommodates necessary operations with limited access but remains hazardous due to restricted airflow.

3. Not Intended for Continuous Human Occupancy

Confined spaces are not designed to support prolonged human presence. For instance:

1. Sewers are accessed only occasionally for repairs or cleaning due to hazardous conditions like toxic gases or poor ventilation.
2. Underground Vaults housing electrical equipment are accessed briefly for maintenance but unsuitable for extended human presence.
3. Flues for transporting combustion gases require worker entry for cleaning or repairs despite being unsafe for continuous occupation.

These conditions create significant risks for workers during even short periods of entry.

4. Remains Confined During Operations

Apart from mainstream confined workplaces, there are some other high-risk confined spaces. For example, airplanes, submarines, or chemical and nuclear laboratories remain confined throughout operations, with no possibility of evacuation until activities cease or conditions change. 

These environments pose unique threats, such as:

1. Exposure to toxic materials in a chemical lab
2. Radiation hazards in a nuclear facility
3. The inability to disembark quickly in the event of disaster

The inability to leave these spaces amplifies the risks, as the environment's operational constraints often limit emergency response. For example, evacuation cannot occur in an aircraft emergency until the plane lands. It significantly delays rescue and response in an event where every second counts.

Types of Confined Spaces

Confined spaces come in various forms, each presenting unique hazards and requiring specific safety measures. Let's discuss the key types of confined spaces:

1. Non-Permit Confined Spaces

Examples: Small storage compartments, attics, and crawl spaces.

These confined spaces meet the essential criteria of being enclosed but do not pose significant hazards. Although these spaces do not require a formal entry permit, workers must still adhere to safety protocols, such as wearing appropriate personal protective equipment (PPE) and maintaining communication with a designated attendant. This ensures preparedness for any unforeseen issues during work.

2. Permit-Required Confined Spaces

Examples: Tanks, silos, and sewers.

Permit-required confined spaces involve one or more significant risks, such as hazardous atmospheres, the potential for engulfment, or entrapment. It requires the following confined space risk assessment control measures:

1. Implementing a documented permit system before entry
2. Detailing safe access and exit procedures
3. Identifying potential risks
4. Outlining control measures such as atmospheric testing and emergency response

3. Restricted Access Spaces

Examples: Elevator shafts, chimneys, and narrow crawl spaces. 

Restricted spaces are designed for limited human entry and require unique access protocols. Depending on the risks present, these locations can fall into either non-permit or permit-required categories. Accessing such spaces demands strict adherence to safety measures, such as proper training and specialized equipment.

4. Confined Elevated Spaces

Examples: Hatches, Tanks, or Silos on roofs, towers, or any other raised platforms

Due to their elevation, confined spaces above ground level pose additional risks. Workers may need to use ladders, stairwells, or lifts to access these areas. Safety protocols, including fall protection systems and heightened awareness of slips, trips, and falls, are critical when working in these elevated spaces.

5. Mechanical Spaces

Examples: Confined compartments housing HVAC systems, electrical wirings, boilers, or turbines

Mechanical confined spaces are often accessed for maintenance or repair. These spaces may fall into non-permit or permit-required categories based on the hazards present, such as moving parts, high temperatures, or high-voltage sources. 

Workers entering mechanical spaces must follow strict safety guidelines, including:

1. Proper lockout/tagout procedures
2. Clearly defined entry and exit protocols
3. Familiarity with Hazard signs for high temperature and voltage

Main Dangers in Confined Spaces

So, what are the hazards of confined spaces, and how can they be prevented for safe and smooth operations? Confined spaces present a range of hazards, many exacerbated by their enclosed nature. 

Let’s quickly look at some common dangers associated with confined spaces.

1. Toxic Atmosphere

A toxic atmosphere can lead to acute health effects such as impaired judgment, unconsciousness, and death. These hazardous conditions often arise due to the presence or release of harmful substances within the confined space. The key causes include:

1. Residue from Previous Use: Toxic substances remaining from earlier storage or processes.
2. Disturbance of Deposits: Sludge or other materials that release harmful gases when disturbed.
3. Internal Combustion: Fires or flames can produce and trap toxic fumes within the space.
4. Improper Isolation: Leakage from adjacent equipment or plant due to inadequate isolation.
5. Work Processes: Welding, cleaning, or chemical reactions releasing harmful vapors.
6. Hidden Contaminants: Release of substances from under scale or brickwork during maintenance or repairs.

2. Oxygen Deficiency

A lack of oxygen can quickly result in asphyxiation, making it one of the most dangerous hazards in confined spaces. The most common reasons for oxygen deficiency are:

1. Gas Displacement: Air displaced by inert or heavier gases such as nitrogen or carbon dioxide.
2. Biological or Chemical Reactions: Processes like organic decay, rusting of metals, or combustion consuming oxygen.
3. Absorption on Surfaces: Damp steel surfaces absorb oxygen from the air, reducing breathable levels.

3. Oxygen Enrichment

Excess oxygen within a confined space significantly increases the risk of fire and explosion. Combustible materials can ignite more easily and burn more intensely in enriched oxygen environments. 

Usually, non-flammable materials in normal air conditions have the potential to ignite spontaneously or burn vigorously.

4. Flammable or Explosive Atmospheres

Flammable substances can create an explosive environment within a confined space. These atmospheres can result from:

• Flammable Gases or Liquids: Vapours from gasoline, methane, or solvents.
• Ignition Sources: Sparks, static electricity, or flames can ignite the flammable gases trapped in the confined space, causing a catastrophic explosion and structural damage.

5. Flowing Liquids or Free-Flowing Solids

Liquids or solids entering a confined space can lead to severe injuries, including suffocation, burns, or drowning. The risks associated with confined spaces as pathways for free-flowing substances include:

• Unexpected Ingress: Sudden inflow of liquids or granular materials.
• Asphyxiating Atmosphere: Dust from disturbed solids can create breathing hazards.

6. Excessive Heat

Confined spaces with high temperatures can cause heat stroke, especially in poorly ventilated environments. The factors contributing to heat-related hazards include:

• PPE Restrictions: Personal protective equipment (PPE) restricting body cooling.
• Inadequate Ventilation: Limited air circulation exacerbates heat buildup.
• Prolonged Exposure: Extended work periods under hot conditions leading to collapse or fatigue.

Steps for Conducting a Confined Space Risk Assessment

Infrastructure Health and Safety Association highlighted specific criteria for performing confined space risk assessments.

A confined space risk assessment is a step-by-step process that identifies and mitigates risks to ensure workplace safety. Below is a quick guide to help you discover what it requires to perform a practical risk assessment for confined spaces.

Step 01 - Identify the Confined Space

The first step is to identify all confined spaces within the workplace. This involves recognizing areas that meet the criteria of being substantially enclosed, presenting hazards, and not designed for continuous occupancy. 

Key considerations during this step include:

• Conduct a walkthrough of the workplace to locate confined spaces such as tanks, silos, or tunnels.
• Maintain records of identified confined spaces, including their specific characteristics and potential hazards.
• Note entry and exit points, ensuring they are appropriately marked for future risk management.

*Documenting these spaces with precise details such as their location, size, and purpose is mandatory. Reliable documentation at the beginning sets the stage for evaluating and managing risks in the following steps.

Step 02 - Evaluate and Assess Hazards

Once confined spaces are identified, assess the potential hazards within each space. 

Components of Evaluation

A thorough hazard evaluation helps prioritize risks and informs the selection of appropriate confined space risk assessment control measures. This evaluation involves four key components:

1. Likelihood Assessment: Determine the probability of a hazard occurring.
2. Severity Assessment: Evaluate the potential impact of the hazard on workers.
3. Risk Rating: Assign a priority level to each hazard based on likelihood and severity.
4. Documentation: Record findings systematically for reference and compliance.

Common Hazards to Assess

The following hazards (that we discussed above in detail) should be evaluated at this stage:

1. Toxic Atmosphere (Presence of harmful gases or vapors)
2. Oxygen Levels (Risks of oxygen deficiency or enrichment)
3. Flammable Atmospheres (Potential for fire or explosions)
4. Physical Hazards (Risks from moving parts, flowing liquids, or free-flowing solids)

Step 03 - Implement Control Measures

Control measures are essential to eliminate or reduce risks associated with confined spaces. These measures include:

Engineering Controls

• Install ventilation systems to maintain air quality.
• Use gas detectors to monitor atmospheric conditions continuously.
• Place physical barriers or guard rails to prevent accidental entry.

Administrative Controls

• Develop standard operating procedures (SOPs) for confined space tasks.
• Implement a permit-to-work system to ensure proper authorization and hazard assessment.
• Schedule work to minimize time spent in confined spaces.

Personal Protective Equipment (PPE)

• Equip workers with respirators, hard hats, and protective clothing.
• Train workers on proper PPE usage and inspection.

Isolation Procedures

• Lockout/tagout (LOTO) systems to prevent accidental activation of machinery.
• Double block and bleed systems to isolate hazardous substances.

Step 04 - Develop Emergency Protocols

Confined spaces require customized emergency response plans to address specific hazards effectively. The following emergency protocols should be no exception and tested regularly when setting a road for effective disaster management:

• Ensure permits detail emergency procedures before entry.
• Provide harnesses, retrieval systems, and breathing apparatus for emergencies.
• Maintain reliable communication systems, such as two-way radios or alarms.
• Assign a trained supervisor to monitor work and initiate emergency responses.

Step 05 - Document Findings and Review Regularly

Maintaining detailed records of risk assessments and regularly reviewing them ensures ongoing safety and compliance. The documentation should be in-depth and cover all the vertical and horizontal details of risks, hazards, precautions, and response systems, and can be done in various formats like:

• Record-Keeping: Document identified risks, control measures, and emergency plans.
• Periodic Reviews: Reassessment of risks when conditions change (such as procurement of new equipment or changes in routine workflows).
• Continuous Improvement: Update procedures and training based on review findings and incident root cause analysis.

How to Reduce the Risk Associated with Confined Spaces

Let’s go through a quick overview of how confined space hazard risk assessment can be done through proper planning and the use of appropriate equipment.

1. Implement Proper Ventilation

Ventilation is critical to maintaining a safe atmosphere inside confined spaces. Proper ventilation ensures harmful gases are removed, oxygen levels are balanced, and the buildup of flammable or toxic substances is minimized. Consider the following proven practices to implement proper ventilation in confined spaces:

1. Pre-Entry Ventilation - Use blowers or fans to purge hazardous gases before entry.
2. Continuous Airflow - Maintain ventilation throughout the operation to prevent atmospheric changes.
3. Monitoring Ventilation Efficiency - Ensure ventilation systems effectively control the environment using gas detectors.

*When ventilation alone cannot create a safe environment (for example, in cases of high worker density in confined spaces or toxic gases), consider adapting additional measures like breathing apparatus.

2. Use Lockout/Tagout Procedures

Lockout/tagout (LOTO) procedures are essential for isolating confined spaces from external hazards such as energy sources or flowing substances. They eliminate the risk of unexpected hazards entering the confined space during operations if you:

1. Disconnect all electrical, pneumatic, hydraulic, and gaseous energy sources.
2. Adapt Methods like blocking pipes, spading, or double-block-and-bleed systems prevent the inflow of hazardous materials.
3. Attach warning tags that indicate the equipment is locked and must not be operated.

3. Monitor Atmospheric Conditions

Continuous atmospheric monitoring is one of the confined spaces' most crucial safety measures. This ensures that any gas or oxygen level changes are detected immediately. It requires:

•    Pre-Entry Testing - Using gas detectors to measure oxygen levels and identify the presence of toxic or flammable gases.
•    Ongoing Monitoring - Continuously monitoring the atmosphere during confined space work.
•    Response to Alarms - Establishing clear protocols for evacuating workers if hazardous levels are detected.

*Monitoring is not a standalone system. It should always be paired with appropriate ventilation and PPE to address potential atmospheric issues.

4. Remove Hazards Before Entry

Prevention is better than a cure. Removing or controlling hazards before entry into a confined space is a proactive approach to safety. It includes:

1. Cleaning or purging the confined space to remove residues, sludge, or flammable materials.
2. Adjusting temperature and humidity to safe levels if excessive heat or moisture is present.
3. Removing ignition sources by setting up an effective fire prevention plan.

5. Provide Personal Protective Equipment (PPE)

PPE serves as the last line of defense when hazards cannot be eliminated or controlled. The recommended direction to use of PPE involves:

1. Ensuring the selected PPE, such as respirators, hard hats, and protective clothing, suits the identified risks.
2. Providing workers with training on PPE's correct use, maintenance, and limitations.
3. Regularly inspecting PPE to ensure it is in proper working condition and certified for use.

*Respiratory protective equipment (RPE) must be worn in environments with atmospheric hazards, including self-contained breathing apparatus (SCBA) if necessary.

6. Establish Emergency Procedures

An effective emergency plan tailored to the specific, confined space is essential to protect workers in the event of an incident. Emergency procedures should include:

1. Rescue Logistics - Plan for efficient rescue operations, including access to rescue equipment and trained personnel.
2. Resuscitation Procedures - Provide equipment and training for CPR and first aid in case of asphyxiation or injury.
3. Communication Systems - Ensure constant communication between workers and a dedicated watchperson outside the confined space.

Emergency plans must be based on a thorough risk assessment of confined places and tested regularly to confirm their effectiveness.

Tools and Resources for Risk Assessment

Conducting a thorough risk assessment for confined spaces requires reliable tools and resources. Checklists and data sheets are essential for systematically identifying hazards and assessing risks. They also help in proper risk assessment documentation and provide rich insights into what changes can be made to secure a confined space to a maximum extent.

Adapting digitization in this domain is also necessary. Software and IoT solutions for confined space risk assessment can streamline the process.

Some recommended tools include:

• Gas detectors for atmospheric monitoring
• Portable ventilation systems
• Lockout/tagout kits for isolating hazards
• Software solutions (such as RiskWatch or Safesite) to manage assessments 

Training Requirements for Confined Space Work

Confined space training ensures workers understand safety protocols and risk assessment techniques.

Employees must be trained to:

• Recognize hazards
• Use personal protective equipment (PPE)
• Follow emergency procedures

Proper training minimizes risks and ensures compliance with regulatory requirements.

It is recommended that you opt for training that also involves emergency response training as part of the disaster management plan. Employees must learn to communicate effectively, evacuate safely, and perform first aid or resuscitation if needed. 

A famous saying is, “The more you sweat in training, the less you bleed in war.” Whether you or your employees have attended training in the past, regular refresher courses are always recommended to maintain competency and keep workers updated on the latest safety practices. 

Check out our Confined Spaces Awareness Training Program, which provides all the training and knowledge you or your employees need to stay compliant and safe while working in confined spaces.

Common Challenges in Conducting Risk Assessments

Conducting confined space risk assessments often encounters several challenges that can compromise the effectiveness of safety measures. 

One of the most significant issues is the need for workers and management to be more aware of the unique hazards associated with confined spaces. 

This can be resolved by outsourcing this crucial aspect to a recognized service provider instead of relying on an internal team. 

Another common obstacle is the presence of cultural barriers within the organization. Some workplaces may resist safety protocols due to time pressures, cost concerns, or a belief that incidents are unlikely. 

This "it won’t happen here" mindset can lead to shortcuts, negligence in risk assessment procedures, or disregarding proper training and safety systems. 

Addressing this challenge requires leadership to actively promote a safety culture and strictly enforce compliance with safety regulations as a non-negotiable standard.

Another critical issue is inadequate training and the need for more expertise among personnel conducting risk assessments. 

With the necessary knowledge and skills, workers can recognize hazards, use proper methods to evaluate risks, and focus on recommended control measures. 

Conclusion

Now you understand why risk assessment for confined spaces is crucial. A detailed confined space risk assessment and the implementation of suitable control measures are much-needed tasks that can't be neglected at any cost.

Remember to discover confined space hazards and precautions in detail, which will further aid you in performing a confined space risk assessment in the right direction.