The hidden dangers of confined spaces cannot be underestimated. A number of people in the UK are killed in confined spaces incidents each year, with many more seriously injured, across a range of industries.
Whilst industries such as oil and gas, utilities and manufacturing may seem the obvious place for confined space working, many facilities have a myriad of hidden spaces that can present a danger to employees. It is important that both facilities managers and employees are aware of what a confined space is to ensure safe working practices.
What the law says
The regulations and the Approved Code of Practice must be considered before any attempt to enter a confined space. The requirements of the Health and Safety at Work etc Act 1974 and the Management of Health and Safety at Work Regulations 1999 would also have to be considered in the preparation of any risk assessment and safe system of work including training as a minimum.
The Approved Code of Practice to the regulations states that ‘the priority when carrying out a risk assessment is to identify the measures needed so that work in confined spaces can be avoided’. Where it isn’t reasonably practicable to prevent work in a confined space, it says ‘the employer or the self employed will need to assess the risks connected with entering or working in the space’. The Confined Space Regulations 1997 places specific requirements on employers managing confined space work. By understanding the risks employers are able to make an informed decision on the correct training, personal protective equipment and safety equipment required to keep employees safe whilst working.
Confined space identification
Confined spaces are found in many places in our working life, some we might expect and some we might not. A confined space is a place that is substantially, though not always entirely, enclosed. It is also a place where there may be a reasonably foreseeable risk from substances or conditions in the space or nearby. It is often a combination of these two circumstances that leads to the increased safety and health risk to confined space workers.
Whilst we normally associate confined spaces with industries such as water, oil and gas, petro-chemical and power generation they can also be found in hospitals, universities and other commercial premises. Sometimes confined spaces in facilities are not easily identifiable. A confined space can be found in almost all buildings, such as the spaces between walls where cables are run, under floor or over head ductwork, unventilated or poorly ventilated rooms and plant rooms where generators are housed.
It is important to provide employees with the correct training so that confined spaces, which may not initially look like a confined space, can be easily identified and workers are aware of the main hazards when working in those spaces. Some of these risks include:
Lack or excess of oxygen
Lack of oxygen can occur, for example, in a laboratory environment where oxygen is driven out by other gases. A normal oxygen level is 20.9% with 19.5% the minimum working level. Anything below this level can quickly affect the functioning of the brain and reduce a person’s ability to respond to his or her environment. Oxygen levels below 16% put employees at risk of unconsciousness or even death. Conversely, excess oxygen presents a serious threat to workers too. Excess oxygen can be caused by leaking equipment and levels over 23.5% increases the risk of fire, particularly in clothing.
Poisonous gas, fume or vapour
Boilers and tanks, activities such as painting, cleaning with degreasers or solvents, chipping off rust, steam cleaning and disturbing sludge can all release poisonous gases, fumes and vapour into the room, creating a dangerous confined space. These gases can be identified using correctly specified atmospheric testing equipment. Consideration should be given to the possibility of gases trapped which may not have been identified by initial atmospheric testing and may also be disturbed and released by someone working in the confined space. Toxic gases, fumes and vapours may contaminate the confined space from the outside, such as from nearby processes or vehicle exhaust fumes. Where work in excavations is taking place then the contamination can come from hazardous substances previously deposited in the ground or from natural sources such as limestone producing carbon dioxide.
Flammable and combustible materials should not be kept in confined spaces unless as part of the work. When required, amounts of flammable material should be kept to a minimum and stored in appropriate containers. The flammable substances can be materials being used to clean the confined space which have a flammable liquid base or from propellant gases of aerosol sprays for example. Where there is a possibility of flammable substances being present in a confined space then suitable equipment, including electrical equipment, will have to be specified to eliminate risk of a spark or ignition source.
The heat can come from areas in an industrial manufacturing plant, such as boilers or an oven that has not had sufficient cooling time before entry. It can also be caused by the use of steam cleaners or hot water high pressure jetting systems. Inadequate ventilation or the lack of chilled ventilation can exacerbate the heat problems in confined spaces.
Reduced physical dimensions
These can be hazardous simply because they can make the way in and out of a confined space difficult to negotiate and make movement inside restrictive. In many buildings spaces between walls, such as where cables and pipeworks are run, may slope inwards or curve and create small spaces that can be difficult to move around in so it is important to be aware of the structure of the building and have the necessary precautions and tools at hand before entering the confined space.
Safety working systems including training
Once the hazards and risks have been assessed the development of a safe working system is essential. It is worth reminding anyone managing confined space working that the first consideration should be identifying a method of doing the work remotely, rather than entering the space. One element of providing a safe working system that is often overlooked is employees with adequate training in confined space entry, which is absolutely crucial. Employers have a legal duty to ensure that a safe system of work is implemented and realistic training should be provided to those working in confined spaces. Specific training for work in confined spaces will depend on an individual’s previous experience and the type of work they will be doing.
It is likely that training will need to cover the need to avoid entry to a confined space, understanding of the work to be undertaken, the necessary precautions that must be taken, understanding safe systems of work and what to do in emergencies. Training should also take into account the practical use of safety features and equipment and involve demonstrations and practical exercises to help participants fully understand the training. Managers and area supervisors, general supervisors, confined space operatives, standby personnel, rescue personnel and anyone involved in confined space risk assessment will need training before working in confined spaces. Consideration should be given to the need to refresh/renew the training periodically, particularly where operatives are not entering confined spaces on a regular basis.
Source: reference guide to the British Safety Industry