What is confined space?

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1 Confined spaces pose dangers because they are usually not designed to be areas where people work. Confined spaces often have poor ventilation which allows hazardous atmospheres to quickly develop, especially if the space is small. The hazards are not always obvious and may change from one entry into the confined space to the next. The risks of working in confined spaces include: loss of consciousness, impairment, injury or death due to the immediate effects of airborne contaminants fire or explosion from the ignition of flammable contaminants difficulty rescuing and treating an injured or unconscious person asphyxiation resulting from oxygen deficiency or immersion in a free-flowing material, such as grain, sand, fertiliser, water or other liquid A confined space is determined by the hazards associated with a set of specific circumstances and not just because work is performed in a small space. A confined space is determined by the structure and a specific set of circumstances. The same structure may or may not be a confined space depending on the circumstances when the space is entered. Entry to a confined space is considered to have occurred when a person s head or upper body enters the space. A space may become a confined space if work that is to be carried out in the space would generate harmful concentrations of airborne contaminants. Temporary control measures such as providing temporary ventilation or achieving a satisfactory pre-entry gas test will not cause a confined space to be declassified. For a confined space to be declassified as a nonconfined space, it needs to have undergone sufficient changes in structure and use to eliminate all inherent hazards that define a confined space. 1

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3 The Confined Space Formula. In order to breakdown the definitions of the Confined Space it is easy to simplify this to the below Confined Space Formula: Confined Space = A + B + C + (D &/or E &/or F &/or G) where; A. The area is enclosed or partially enclosed space B. Is not designed or intended primarily to be occuplied by a person C. Is, or is designed or intended to be, at normal atmospheric pressure while any person is in the space D. The atmosphere does not have safe oxygen levels E. Harmful concentrations of airborne contaminants F. Risk of fire or explosion from contaminants including airborne gases, vapours and dusts G. Risk of engulfment In order to be classified to be a confined space, the space must have A, B & C, aswell as one or more of D, E, F & G. Appendix A of the Code of Practice, gives a practical use to this type of classification criteria in how to judge whether the space is defined as a confined space. Getting Started There are three essential documents that need to be produced before undertaking work in a confined space. These documents are: A Risk Assessment An Entry Permit A Rescue and Emergency Plan Entry Permit: Completed by a competent person Be in writing Specify: o The confined space which the permit relates to o The names of the pesons permitted to enter the space o The period of time during which the work in the space will be carried out o Measures to control risk associated with the proposed work in the space Contain space for an acknowledgement that the work in the confined space has been completed and that all persons have left the confined space. 3

4 Producing these documents is a team effort, and there are different roles within this team that have key responsibilities: Authoriser Competent Person Stand By Person / Sentry Worker Issue writen authority for the entry permit and state the period of validity of the permit Ensure all workers have left the confined space before cancelling the permit Complete the entry permit Conduct a risk assessment Review and revise risk assessment Participate and assist in the completion of the risk assessment and rescue plan documentation Rehurse rescue plan with team prior to entry Remain outside or in close proximity to the confined space Ensure compliance with permit conditions Maintain the log of those inside the space Continuously communicate with those working in the confined space Monitor safety of those working in the confined space Monitor equipment external to the confined space Raise the alarm & implment rescue procedures from outside the confied space Order entrants out of the confined space should hazards or controls change Participate and assist in the completion of the risk assessment and rescue plan documentation Rehurse rescue plan with team prior to entry Obey all permit conditions Take instructions from the stand by person Continuously monitor atmospheric conditions within the confined space Continuously communicate with the stand by person Must take resonable care of their own health and safety and that their work does not adversely affect the health and safety of other persons. Workers must comply with any reasonable instructions given relating to the confined space entry permits, risk control measures and emergency procedures, and should carry out work in a confined space in accorance with any relevant information and training provided to them. This does not necessarily mean that a confined space operations requires four team members, but at least two people are required to take responsibility for each of these roles. 4 It is compulsary for the confined space to have signs and protective barriers to pevent entry of persons not involved in the tasks. A commonly used sign is the one seen below.

5 How to Manage the Risks Associated with a Confined Space Common hazards found in confined spaces: Restricted entry or exit Harmful airbourne contaminants Unsafe oxygen levels Fire or Explosion Engulfment Uncontrolled introduction of substances Biological hazards Mechanical hazards Electrical hazards Skin contact with hazardous substances Noise Manual handling tasks Radiation Environmental hazards Hazards outside the confined space Additional physiological and psychological demands 5