Image source: safetysupplywarehouse.com
Places with limited entry and exit are defined as such for a specific reason and usually this has to do with a hazard or number of hazards which not all workers need to be exposed to.
Although work on a construction site in general does carry its risks, work in areas where access is restricted is usually even more dangerous. In fact these spaces with limited access are usually confined spaces such as trenches, tunnels, excavations and shafts. Actually all the hazards present in a regular workspace can be even more hazardous in a confined space which is why safety information is necessary for working in confined spaces.
Usually the confined space has restricted or limited access for entry and exit and the atmosphere may contain potentially harmful levels of contaminant/s which may cause asphyxiation.
The risk associated with working in these spaces is that these contaminants may be flammable or may not have a safe level of oxygen. Another possible danger when working in confined spaces is engulfment from a liquid or free flowing solid – it is for this reason that its’ best for access into these spaces to be restricted.
Some of the general hazards associated with confined spaces include atmospheric/respiratory hazard, oxygen deficiency, fires, biological hazards, physical configuration, electrical and mechanical hazards, thermal and radiation hazards, noise and vibration, engulfment or entrapment.
The precautionary measures that need to be taken before entering a confined space depend on what the hazards and risks are most likely to be. Tests should be carried out by appropriately trained individuals before entering a confined space to determine the nature and extent of the hazard.
It is important for construction workers to remember not to enter a confined space unless fully trained and authorised to do so. Confined space entry and exits are a particularly important area to address.
The risk associated with work in a confined space was highlighted by an incident which occurred in an underground chamber in Belgium earlier this month. SafetyNews.co.uk posted this about the incident:
A construction worker died and a colleague was seriously injured in an apparent confined space accident as they were removing formwork at the site of a new police station on Kioskplaats in Hoboken, near Antwerp.
Almost daily we hear of workers who are killed while working in a confined space and usually the cause has something to do with poisonous gases, bad air quality or lack of proper ventilation.
There may be an insufficient amount of oxygen for the worker to breathe especially in areas that aren’t properly ventilated. The atmosphere might contain vapours of a poisonous chemical that could make the worker ill or even cause the worker to lose consciousness. Natural ventilation alone will often not be sufficient to maintain breathable quality air. If this is a hazard identified, measures need to be introduced to manage this hazard.
Although work in a confined space may seem like it is fairly “safe” there are a number of risks associated with this work environment that may not be evident initially and need to be identified and managed accordingly to avoid tragic and unnecessary consequences.