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October 7, 2015

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Ensuring safe working in confined spaces

Hamburg-Training-Centre-launch-demo55RStephen Morris, Training Sales Manager with Capital Safety Training UK looks at the safety of workers in confined spaces.

The publication earlier this year of a revised Approved Code of Practice (ACOP) for the Confined Spaces Regulations 1997 offers the ideal opportunity to review policies, procedures and competences for situations where employees are required to work in a confined space, particularly as there can be some debate or confusion over what specifically defines a confined space. Part of that review should also consider the implications of the access and work activities to be undertaken within the confined space. This could include the method of access and provisions for working at height and should always ensure compliance with other relevant statutory requirements.

The Health & Safety Executive (HSE) defines a confined space as an area that is substantially, although not always entirely, enclosed and where serious injuries can occur from hazardous substances or conditions such as lack of oxygen within the space. Confined spaces can take many forms including silos, storage tanks, reaction vessels, sewers and enclosed drains, open topped chambers, vats and ductwork.  The specified risks associated with working in such spaces are defined as:

  • The serious injury to any person at work arising from a fire or explosion;
  • The loss of consciousness arising from an increase in body temperature;
  • The loss of consciousness or asphyxiation arising from gas, fume, vapor or the lack of oxygen;
  • The drowning of any person at work arising from an increase in the level of liquid;
  • The asphyxiation of any person at work arising from a free flowing solid; or
  • The inability to reach a respirable environment due to entrapment by a free-flowing solid.

These risks may be inherent because of the nature or purpose of the enclosed space or they could be introduced by the activity being undertaken within the space.  For example, a vessel which has been used to contain solvent would probably have an existing significant risk from explosion, fire or low oxygen levels.  On the other hand, a drained and isolated water tank may have little in the way of an identifiable specified risk in itself, but if the work to be carried out involves a function such as welding, a significant risk of explosive gases, oxygen depletion, toxic fumes or increase in body temperature is being introduced.

To assist in the identification of confined spaces, the new ACOP includes a flow chart designed to steer the user towards the right conclusion and, hopefully, avoid any confusion or misinterpretation.  Other additions include a new section on actions for workspaces with a reduced oxygen concentration and an alignment with the Control of Substances Hazardous to Health Regulations 2002 for a requirement for fit testing of respiratory protective equipment.

Assessing the risk

Under the Management of Health and Safety at Work Regulations 1999, a suitable and sufficient assessment must be carried out for all work activities to determine what measures are necessary for safety.  In relation to work in confined spaces, this involves identifying the hazards present, assessing the risks and deciding on the appropriate control measures.  Generally, the assessment will mean looking at the task, the working environment, working materials and tools, the suitability of those carrying out the task and arrangements for emergency rescue.

here the assessment identifies risks of serious injury, the Confined Spaces Regulations 1997 apply, and these contain the following key duties:

  • Where possible, avoid the need to enter a confined space by carrying out the work from outside
  • If working within the confined space is unavoidable, follow a safe system of work and
  • Ensure that adequate emergency arrangements are in place before the work starts

In the course of assessing the risks, and depending on the working environment, it is quite likely that the requirements of other health and safety regulations, such as the ‘Provision of Personal Protective Equipment (PPE) Regulations may need to be addressed.

Working at height

Under the Working at Height Regulations 2005, someone can be considered to be working at height in any place, including at or below ground level, where there is a risk of a person falling a distance likely to cause an injury the measures required by these Regulations must be in place.

When assessing the risk of a fall from an access point, it is not only the person carrying out the work that needs to be taken into consideration – it is anyone who might be in the area of that access point.  In cases where workers are accessing drains or service tunnels via a manhole, this could include members of the public.  In terms of risk control, the best way to protect a person from a fall is to remove or exclude them from the risk area.  So, any person not needing to be exposed to the fall risk should be excluded by use of physical barriers and signage.

For anyone who needs to be in the vicinity of the risk area, the options to prevent a fall using fall prevention equipment must be taken into consideration. This usually means the use of harness and work restraint systems attached to suitable anchor points. The final option is fall arrest equipment using a suitable fall arrest lanyard or self-reeling lifeline (SRL).

Falls while entering or exiting confined spaces are common, often resulting from the use of poorly maintained climbing structures, poor lighting or space restrictions.  For workers who have to access the area at height, usually the only option that provides protection from injury in the case of a fall is fall-arrest equipment.  Personal fall arrest systems incorporate three components, often described as the ABCs of fall protection, which are an anchorage/anchorage connector, body support and connecting device.

In some situations, it may be necessary to use suspended access techniques to lower the worker into the confined space using a davit and winch.  In this case, the back-up of an SRL fall arrest system is also necessary and it is common practice to use a retrievable type of SRL to offer the capability of rescue in the event the worker gets into difficulty whilst in the confined space.

In case of emergency

As previously stated, plans for working in a confined space should always include provision for rescue should an accident occur and the worker involved is unable to exit the area unaided. Circumstances will always differ and methods of rescue need to take into account the specific hazards to both victim and rescuers involved.  However, in many situations, a non-entry rescue is the safest solution for all parties and the only time an entry rescue should be attempted is when the use of a non-entry technique is likely to place the injured or trapped worker in greater danger.

In general, it is safe to say that rescues from confined spaces – particularly those with difficult or at-height access – are too complicated and dangerous for untrained or non-experts to attempt. Emergency services and industrial entry specialists are highly trained in rescue strategies and the use of specialised equipment that may be critical to the survival of a trapped or injured worker. In any situation which leads to the need for rescue, obviously speed of reaction is of the essence which underlines the importance of having a ready-prepared, comprehensive plan in place. A sensible precaution is to have designated competent people who can quickly perform their assigned rescue duties if an emergency occurs and it is the employer’s responsibility to ensure that these individuals are suitably trained and equipped.

Working in confined spaces, particularly when combined with the need to access or work within them at height, poses risk, but risk can be managed if the correct strategies are in place. By taking the time to review the appropriate legislation and the guidance offered by the HSE, employers can ensure that they are, to the best of their ability, providing a safe working environment where the risk of death or serious injury is minimised.

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