Working in a confined space requires the use of appropriate fall protection equipment, together with proper training and instruction. There is a good reason for this: every year, around 90 people lose their lives while working in confined spaces. These figures underline the importance of working safely. In this article, we outline some of the key principles for safe working in confined spaces.
Working in confined spaces
Every confined space is different and requires a site-specific risk assessment and approach. Nevertheless, two essential steps apply to every confined space entry:
Always work with a standby person. This person must remain outside the confined space and be capable of initiating or assisting with a rescue in the event of an emergency. Everyone involved—including the standby person—must wear the appropriate personal fall protection equipment where required.
Assess all hazards before entry. Check for hazardous gases, oxygen deficiency or enrichment, and any other atmospheric hazards. Ventilate the confined space where necessary and, wherever possible, ensure that entrants carry a personal multi-gas detector throughout the work.
Entering confined spaces
In most cases, there are two safe methods for entering a confined space: using fixed steps or a portable ladder, or using a personnel winch. In both cases, a backup fall arrest device with an integrated rescue function must be used.
Before entering the confined space, always verify that the full body harness, anchor point, and fall arrester with rescue capability are in good working order. The anchor point is typically provided by a tripod or 5-piece davit system, although some sites are equipped with permanent anchor points above the access opening.
Entry using fixed steps or a portable ladder
Access may be gained using fixed ladder rungs or a portable ladder, such as a rope ladder or a ladder inserted through a manhole opening.
In these situations, a fall arrester with an integrated rescue winch is always required. A standard fall arrester without a rescue function is not sufficient. While a fall arrester will stop a fall, it cannot recover a person who is unable to climb out independently. The integrated rescue winch allows the casualty to be safely lifted back to the surface.
Please note: The rescue winch may only be used for emergency rescue. It must not be used for routine lifting or lowering of personnel.
Entry using a personnel winch
Where no fixed steps or ladder are available, personnel should be lowered using a personnel winch specifically designed and certified for lifting and lowering people.
As a backup, an independent fall arrester with an integrated rescue function must always be used in case the personnel winch fails.
What about toxic gases?
Why is atmospheric testing for oxygen levels and hazardous gases essential before entering a confined space? Because oxygen deficiency is the leading cause of accidents and fatalities in confined spaces. Many hazardous gases displace oxygen, creating an oxygen-deficient atmosphere. In addition, inhaling toxic gases can be extremely dangerous in itself. It is estimated that one in four confined spaces contains hazardous or toxic gases.
You should also consider whether the work itself could generate hazardous gases. Welding, for example, produces fumes that can quickly accumulate in confined spaces.
Whenever possible, a confined space should be ventilated before entry. In some situations, continuous mechanical ventilation is required throughout the work.
Depending on the hazards identified in the risk assessment, workers should also wear the appropriate respiratory protective equipment (RPE).
Rescue in a confined space
If you need to rescue a colleague from a confined space, you may be exposed to the same hazards as the casualty, including oxygen deficiency or toxic gases. That is why every confined space operation should have a carefully prepared rescue plan.
A rescue must be carried out as safely and carefully as possible. This can be complex, as moving the casualty may be difficult or painful. If the person is unconscious, it may also be challenging to manoeuvre them through a narrow manhole. Even so, they must be recovered as quickly as possible. Depending on the situation, a third person may be required to assist with the rescue.
Rescue equipment for confined spaces
Suitable rescue equipment must always be readily available. Important examples include a foldable rescue stretcher, often known as a Sked, and the shorter Half-Sked version.
A Sked is wrapped tightly around the casualty, reducing their profile so they can be recovered through a narrow opening. It can also be used to drag a casualty back towards a manhole if they have become disconnected from the backup system.
The Half-Sked is designed for confined spaces that are not only narrow but also difficult to navigate, such as reactor vessels or other spaces with bends and restricted access.
Task risk assessment for confined spaces
A Task Risk Assessment (TRA) helps the team prepare for working safely in a confined space. Every confined space presents different hazards and practical challenges, so clear arrangements made in advance can prevent serious incidents.
A TRA can be completed in three steps:
Describe each stage of the work process.
Identify the risks associated with each stage.
Agree on clear control measures with the team to reduce those risks.
One practical control measure is to connect the backup fall arrest device with rescue function to the rear attachment point of the harness. If a worker loses consciousness, their head will naturally fall forwards, making it easier to recover them from the confined space.
Proper training is essential
The risks associated with confined space work are significant. Fortunately, workers can be trained to recognise these hazards and respond correctly in an emergency.
Training in the use of personnel winches and fall arrest devices with rescue functions is mandatory. In confined space access and rescue operations, all safety and rescue equipment must work quickly, reliably, and without failure.
Request a training
Working in confined spaces requires specialised fall protection equipment. Employers are responsible for ensuring that employees receive the appropriate training to use this equipment safely and carry out confined space work correctly. Contact us to learn more about our training programmes and expert advice.
Podcast summary: working safely in confined spaces
Confined spaces require special attention when it comes to safety and operational efficiency. These are fully or partially enclosed spaces that are not designed for continuous occupancy and are often difficult to access. Examples include silos, storage tanks, sewers, and excavations.
The greatest challenges when working in confined spaces are gaining safe access and ensuring that workers can be evacuated quickly in the event of an emergency. Other significant hazards include hazardous gases, oxygen deficiency, heat stress, and risks associated with electrical equipment.
Before any work begins, it is essential to assess the conditions on site and implement the appropriate safety measures. This includes ventilating the confined space where necessary and continuously monitoring the atmosphere using suitable gas detection equipment.
Proper training and the correct use of personal protective equipment (PPE) are also critical. Training can be delivered either on-site at the customer's location or in dedicated training facilities designed to simulate confined space working conditions.
