Confidential space

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# Why is working in a confined space more hazardous than working in other workspaces? (cont.) ## How is air quality maintained? (cont.) - Care should be taken to make sure the air being provided by the ventilation system to the confined space is 'clean' throughout the entire space. - Ease of air movement throughout the confined space should be considered because of the danger of pockets of toxic gases still remaining even with the use of mechanical ventilation. - Do not substitute oxygen for fresh air. Increasing the oxygen content will significantly increase the risk of fire and explosion. - The use of mechanical ventilation should be noted on the entry permit. - Ensure air being removed from the confined space is exhausted away from workers on the outside. ## How are fire and explosion prevented? Work where a flame is used or a source of ignition may be produced (hot work) should not normally be performed in a confined space unless: - All flammable gases, liquids and vapours are removed before the start of any hot work. Mechanical ventilation is usually used to 1. Keep the concentration of any explosive or flammable hazardous substance to a level that does not create an explosion hazard, for example less than 5% or 10% of its Lower Explosive Limit (These numbers can vary slightly from jurisdiction to jurisdiction.) AND 2. Make sure that the oxygen content in the confined space is not enriched. Oxygen content should be less than 23% but maintained at levels greater than 19.5%. (These numbers can vary slightly from jurisdiction to jurisdiction.) - Surfaces coated with combustible material should be cleaned or shielded to prevent ignition. - Do not bring fuel or fuel containers into the confined space (e.g., gasoline, propane), if possible. Ensure welding equipment is in good condition. - Where appropriate, use spark-resistant tools, and make sure all equipment is bonded or grounded properly. While doing the hot work, the concentrations of oxygen …

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# Confined Space - Program (cont.) ## What is a Confined Space Hazard Assessment and Control Program? (cont.) - Development of an emergency plan complete with training and equipment in case an unforeseen situation occurs. - An emergency response system. - Reporting and investigating incidents related to work in confined spaces. - Record and documentation control. - Program review whenever there is a change in circumstances or at least annually, to identify program weaknesses and make any necessary changes to the program. More information about confined spaces is located in the OSH Answers documents Confined Spaces - Introduction and Confined Space - Atmospheric Testing. ## What is an Entry Permit System? An entry permit is an administrative tool used to document the completion of a hazard and risk assessment for each confined space entry. Someone fully trained and experienced in confined space work should complete the entry permit. Some jurisdictions require a permit for all confined space entries. An entry permit is required for confined spaces where the hazard and risk assessment determined that the measures to control the risk involve the following: - atmospheric monitoring, - isolation, - lockout, - ventilation, - safeguarding devices, - respiratory protection, or - any other control that needs to be verified and documented in the permit as required by the assessment. Before entering a confined space, an entry permit should be completed. It should contain at least the following information: - The length of time the permit is valid for. - The name(s) of the worker(s) that are authorized to enter the confined space. - The name(s) of the attendant(s) (safety watch). - The name of the supervisor responsible for the work. - The location and description of the confined space. Confined Space - Program CCOHS

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# Confined Space - Program (cont.) ## What should happen when work is being done in a confined space? (cont.) - Understands the nature of the hazards that may be found inside that particular confined space and can recognize signs, symptoms and behavioural effects that workers in the confined space could experience. - Monitors the confined space and surrounding area and is on the look out for dangerous conditions. - Remains outside the confined space and does no other work which may interfere with their primary duty of monitoring the workers inside the confined space. - Maintains constant two-way communication with the workers in the confined space. - Orders the immediate evacuation if a potential hazard, not already controlled for, is detected. - Calls for emergency assistance immediately if an emergency develops. - Is immediately available to provide non-entry emergency assistance when needed. - Can provide entry rescue only after the most stringent precautions are taken and another attendant is immediately available to assume the attendant duties Should a worker leave a confined space for a short time (for example, coffee break, getting additional material for their work), the confined space should be re-tested before the worker re-enters. If the confined space has been continuously monitored by equipment that can show the details of the atmosphere during the time absent from the confined space and this information can be seen from outside the confined space, it can be re-entered without retesting. If there is no continuous air monitoring then the hazard assessment needs to be repeated. No confined space should be closed off until it has been verified that no person is inside it. After exiting the confined space, the time of exit should be noted on the entry permit. ## What are some emergency response precautions? The detailed plan for emergency response to an injury or other emergency within the confined space should be described in detail in the…

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# Confined Space - Program (cont.) ## What is an Entry Permit System? (cont.) - The scope of the work that is to be done in the confined space. - Possible hazards that may be encountered inside and outside the space. - Possible hazards that may develop during the work activity. - The date and time of entry into the confined space and the anticipated time of exit. - The details of any atmospheric testing done of the confined space - when, where, results, and date monitoring equipment was last calibrated. Ideally, calibration (including bump test) would be done just before each use. If this is not possible, follow the equipment manufacturer's guidelines for the frequency of calibration. - Hazard control measures, including the use of mechanical ventilation, work procedures, personal protective equipment needed and any other precautions that must be followed by every worker who is going to enter the confined space. - Means of communication between the persons working in the confined space and the attendant. - Emergency plan, and the protective equipment and emergency equipment to be used by any person who takes part in a rescue or responds to other emergency situations in the confined space - A signature of a worker who did the confined space air testing. The signature on the permit would indicate that adequate precautions are being taken to control the anticipated hazards. - Authorization signature by the supervisor certifying that the space has been properly evaluated, prepared, and it is safe for entry and work. The entry permit should be posted at the confined space and remain so until the work is completed. The employer should keep a copy of the completed permit on file. ## What should happen when work is being done in a confined space? Use warning signs to prevent unauthorized entry to the confined space. Anyone working in a confined space must be constantly alert for any changing conditions within the confined space. In the event of an alarm fr…

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# Why is working in a confined space more hazardous than working in other workspaces? (cont.) Lack of communication between the workers in the space, the attendant and the emergency response team. ## What should be done when preparing to enter the confined space? The important thing to remember is that each time a worker plans to enter any work space, the worker should determine if that work space is considered a confined space. Be sure the confined space hazard assessment and control program has been followed. Please see the OSH Answers document Confined Space - Program for more information. The next question to ask is - Is it absolutely necessary that the work be carried out inside the confined space? In many cases where there have been deaths in confined spaces, the work could have been done outside the confined space! Before entering any confined space, a trained and experienced person should identify and evaluate all the existing and potential hazards within the confined space. Evaluate activities both inside and outside the confined space. Air quality testing: The air within the confined space should be tested from outside of the confined space before entry into the confined space. Care should be taken to ensure that air is tested throughout the confined space - side-to-side and top to bottom. Continuous monitoring should be considered in situations where a worker is in a space where atmospheric conditions have the potential to change (e.g., broken or leaking pipes or vessels, work activities create a hazardous environment or isolation of a substance is not possible). A trained worker using detection equipment which has remote probes and sampling lines should do the air quality testing. Always ensure the testing equipment is properly calibrated and maintained. The sampling should show that: - The oxygen content is within safe limits - not too little and not too much. - A hazardous atmosphere (toxic gases, flammable atmosphere) is not present. - Ventil…

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# What is a confined space? Generally speaking, a confined space is a fully or partially enclosed space that: - is not primarily designed or intended for continuous human occupancy - has limited or restricted entrance or exit, or a configuration that can complicate first aid, rescue, evacuation, or other emergency response activities - can represent a risk for the health and safety of anyone who enters, due to one or more of the following factors: - its design, construction, location or atmosphere - the materials or substances in it - work activities being carried out in it, or - the mechanical, process and safety hazards present Confined spaces can be found in almost any workplace. Confined spaces can be below or above ground. A confined space, despite its name, is not necessarily small. Examples of confined spaces include silos, vats, hoppers, utility vaults, tanks, water supply towers, sewers, pipes, access shafts, truck or rail tank cars, aircraft wings, boilers, manholes, pump stations, digesters, manure pits and storage bins. Ditches, wells, and trenches may also be confined spaces when access or egress is limited (but they still have "blue sky" above). Barges, shipping containers and fish holds are also considered as possible confined spaces. Tunnels Wells Manholes Cold Storage Ship Holds Subcellars Tanks Culverts Silos Vaults Open Ditch Confined Space - Introduction CCOHS

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# Confined Space - Program (cont.) ## What are some emergency response precautions? (cont.) Rescue the victims from outside of the confined space, if possible. No worker should enter a confined space to attempt a rescue unless that worker is fully trained in the rescue procedures and is wearing the appropriate personal protective equipment. More than 60% of deaths in confined spaces are would-be rescuers, who are not fully trained and adequately equipped. An attendant should remain outside the confined space to monitor the space while there are rescue procedures taking place. Rescue personnel should not use the same air as the confined space workers they are rescuing. Wear SCBA (self-contained breathing apparatus) or supplied air respirator with an escape bottle where possible. Personnel who can provide first aid and cardio-pulmonary resuscitation (CPR) are also required. These persons can be the attendant or other rescue personnel, as long as providing first aid or CPR does not interfere with their other duties (requirements may vary depending on the jurisdiction). ## How many people must be present while work is being done in a confined space? Some jurisdictions require a certain number of workers be present. For example, New Brunswick requires three - the entrant, a person standing at the entrance (attendant), and a back-up employee within sight and shouting distance with no obstructions or barriers to overcome to reach the space (for example, not in another room or a parking lot). Each person has to be trained to carry out their responsibilities. Confined Space - Program CCOHS