The Hierarchy of Controls: A Blueprint For Safety in Confined Spaces
A Guide to Working in Confined Spaces: Part 3
Introduction
In Chapter 2 of this series, we discussed the important role that risk assessments play when working in confined spaces. Today in Chapter 3, we will be focusing on step 3 of the risk assessment process - evaluating risks and implementing control measures.
In this article, we will cover:
The Hierarchy of Controls and;
How they can be applied to working in confined spaces
Introduction to The Hierarchy of Controls
The Hierarchy of Controls is a system used in occupational health and safety, its purpose is to determine which measures are most suitable to reduce or remove hazards. Although confined spaces themselves are inherently hazardous environments, the Hierarchy of Controls provides a systematic approach to dealing with hazards. Through understanding and implementing these control measures, employers and employers can create safe systems of work to mitigate the risks associated with these environments in turn, ensuring the safety of everyone involved.
The Hierarchy is structured as an inverted pyramid, starting with the most effective measures, and down to the least effective measures:
Elimination
Elimination is the most preferable control measure because it involves removing the hazard entirely which means no exposure can occur to begin with.
Substitution
Substitution is used when elimination is not reasonably practicable. It involves minimising the risks by replacing the task itself or changing the work process.
Engineering Controls
Engineering controls change the hazard at its source and involve either modifying the work activities or the workspace itself to reduce or prevent workers from being exposed.
Administrative Controls
Administrative controls involve the development of safe work procedures, these controls are focused on organising work in a way that minimises exposure to hazards.
Personal Protective Equipment (PPE)
If the measures above have been implemented and have been insufficient in controlling the risk, PPE is used as the last line of defence.
Using The Hierarchy of Controls for Confined Space Work
Elimination
As stated in the Confined Spaces Regulations 1997, no person at work shall enter a confined space to carry out work for any purpose unless it is not reasonably practicable to achieve that purpose without such entry.
Substitution
The duty holder should question: Is the intended work really necessary, or could:
The confined space itself be modified so that entry is unnecessary or;
Could the work be done from outside?
Examples of modifying work practices to avoid the need for entry into a confined space include:
Cleaning/removing residues from the space from outside e.g. using high-pressure jets
Using remote visual inspections to examine the space e.g. drones
Clearing obstructions in silos e.g. using mechanical equipment or vibration devices
Testing the atmosphere using specialised equipment e.g. gas detectors
Using built-in measures that allow you to see what is happening within the space without entering e.g. CCTV systems
Engineering Controls
If it isn’t possible to avoid entry into the confined space, engineering controls should be put in place. Examples of engineering controls include:
Installing an effective ventilation system to reduce risks associated with oxygen-deficient environments
Ensuring safe entry and exit points are put in place so that workers and rescue teams have easy access and egress e.g. well-secured ladders, stairs or ramps with handrails
Installing sufficient lighting to improve visibility and reduce the likelihood of slips, trips and falls
Implementing communication systems so that workers can maintain contact with those situated outside
Installing guardrails, barriers or fall arrest systems to prevent falls from height
Providing appropriate rescue equipment e.g. hoists, winches, safety harnesses or retrieval systems
Administrative Controls
Although they are not as effective as engineering controls or substitution, administrative controls play an important role in increasing overall safety and work to complement the control measures listed above. Examples of administrative control include:
Implementing a permit-to-work system to ensure that only trained and competent workers enter confined spaces
Ensuring that any other relevant work permits are filled out (e.g. a hot works permit if welding activities are taking place within the confined space)
Providing workers with sufficient training to ensure they are aware of hazards, emergency procedures, communication protocols and safe work practices.
Assigning a competent supervisor that is trained to respond to emergencies and ensure they remain situated outside of the confined space
Ensuring that pre-entry checks take place (e.g. checking the atmospheric conditions before confined space entry)
Developing emergency procedures and ensuring that all workers are aware of the emergency drills
Personal Protective Equipment (PPE)
The specific PPE requirements are dependent on a couple of variables:
The nature of the confined space
The work activities being carried out and the specific hazards identified with the activities
Some common PPE required in confined spaces includes but is not limited to:
Respiratory Protective Equipment (RPE): RPE may be required if there’s a risk of exposure to hazardous substances and/or work is taking place in an oxygen-deficient atmosphere
Fall Protection Equipment: Workers may require fall protection e.g. harnesses if work at height is taking place.
Hearing Protection: If the worker is using or is situated near noise-generating equipment, hearing protection e.g. ear defenders may be required.
Head Protection: Workers may require head protection e.g. hard hats if there is a risk of falling objects or other overhead hazards.
Conclusion
In the world of confined space work, applying a meticulous and systematic approach to safety is key. The Hierarchy of Controls offers a thorough step-by-step strategy to implement safe systems of work. Continuous monitoring, regular risk assessments, and staying informed of changes to industry standards all play an integral part in maintaining safety.