Confined space safety toolbox talk

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# Why is working in a confined space more hazardous than working in other workspaces? (cont.) ## How are fire and explosion prevented? (cont.) Continuous Monitor for Oxygen and Combustible Gases If potential flammable atmosphere hazards are identified during the initial testing, the air in the confined space should be cleaned or purged, ventilated and then tested again before entry to the confined space is allowed. Only after the air testing is within allowable limits should entry occur as the gases used for purging can also be extremely hazardous. ## How are energy sources controlled? All potentially hazardous energy sources such as electrical, mechanical, hydraulic, pneumatic, chemical, or thermal must be de-energized (or isolated) and locked out prior to entry to the confined space so that equipment cannot be turned on unintentionally. If de-energization is not possible, the hazardous energy must be controlled in a way that eliminates or minimizes worker exposure to the hazards before workers are allowed to enter the confined space. It is important that any method of control other than isolation and lockout must be evaluated and the effectiveness for controlling the hazardous energy must be demonstrated. Please see the OSH Answers on Hazardous Energy Control Programs and Lockout/Tag_out for more information. ## What are other safety precautions? Many other situations or hazards may be present in a confined space. Be sure that all hazards and risks are identified and controlled, for example: - Any liquids or free-flowing solids should be removed from the confined space to eliminate the risk of drowning or suffocation. - All pipes should be physically disconnected or isolation blanks bolted in place. Closing valves is not sufficient. - Use two blocking valves, with an open vent or bleed valve between the blocking valves when isolating pipelines or similar conveyances to prevent entry of materials and hazardous contaminants. - A barrier is present to p…

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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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CCOHS CCHST Canadian Centre for Occupational Health and Safety Centre canadien d'hygiène et de sécurité au travail Confined Space # Confined Space - Introduction ## On this page Is working in a confined space hazardous? What is a confined space? What are the hazards in a confined space? Why is working in a confined space more hazardous than working in other workspaces? What should be done when preparing to enter the confined space? How are hazards controlled in confined spaces? How is air quality maintained? How are fire and explosion prevented? How are energy sources controlled? What are other safety precautions? ## Is working in a confined space hazardous? Many workers are injured and killed each year while working in confined spaces. An estimated 60% of the fatalities have been among the would-be rescuers. A confined space can be more hazardous than regular workspaces for many reasons. To effectively control the risks associated with working in a confined space, a confined space hazard assessment and control program should be implemented for your workplace. Before putting together this program, make sure to review the specific regulations that apply to your workplace. All jurisdictions within Canada have regulations dealing with confined space entry. The regulations can vary slightly from jurisdiction to jurisdiction. A contact list for the jurisdictions is available in the OSH Answers document Canadian Government Departments Responsible for Health and Safety.. More information about the confined space control program is located in the OSH Answers document Confined Space - Program and Confined Space - Atmospheric Testing. If the confined space cannot be made safe for the worker by taking precautions then workers should NOT enter the confined space until it is made safe to enter by additional means. All confined spaces should be considered hazardous unless a competent person has determined otherwise through a risk assessment. Confined Space - Intr…

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# What are the hazards in a confined space? All hazards found in a regular workspace can also be found in a confined space. However, they can be even more hazardous in a confined space than in a regular worksite. Hazards in confined spaces can include: - Poor air quality: - Insufficient amount of oxygen for the worker to breathe. - Toxic gases that could make the worker ill or cause the worker to lose consciousness. Examples include hydrogen sulphide and carbon monoxide). - Asphyxiants - simple asphyxiants are gases which can displace oxygen in the air (normally about 21 percent). Low oxygen levels (19.5 percent or less) can cause symptoms such as rapid breathing, rapid heart rate, clumsiness, emotional upset, and fatigue. As less oxygen becomes available, nausea and vomiting, collapse, convulsions, coma and death can occur. Unconsciousness or death could result within minutes following exposure to a simple asphyxiant. Simple asphyxiants include argon, nitrogen, or carbon dioxide. - Chemical exposures due to skin contact or ingestion (as well as inhalation of toxic gases). - Fire hazard - An explosive or flammable atmosphere due to flammable liquids and gases and combustible dusts which, if ignited, would lead to fire or explosion. - Process-related hazards - such as residual chemicals, or release of contents of a supply line. - Physical hazards - noise, heat, cold, radiation, vibration, electrical, and inadequate lighting. - Safety hazards - such as moving parts of equipment, structural hazards, engulfment, entanglement, slips, or falls. - Vehicular and pedestrian traffic. - Shifting or collapse of bulk material (engulfment). - Barrier failure that results in a flood or release of free-flowing solid or liquid. - Visibility - such as smoke particles in the air. - Biological hazards - viruses, bacteria from fecal matter and sludge, fungi, or moulds. Confined Space - Introduction CCOHS

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# Confined Space - Program (cont.) ## How many people must be present while work is being done in a confined space? (cont.) Other jurisdictions describe the qualifications that must be fulfilled, which may vary in the number of people present. For example, Ontario describes this requirement as having an adequate number of persons trained in the following to be immediately available to begin on- site rescue procedures as required: - On-site rescue procedures - First aid and CPR - Use of the rescue equipment required by the confined space plan. ## Is worker training important? Yes, appropriate training is extremely important to working safely in confined spaces, as well as for attendant and rescue personnel. Hands-on training should be an essential part of the confined space training. Every worker that enters a confined space must be fully trained on the following: - Recognition and identification of potential hazards associated with the confined spaces that will be entered. - Evaluation and control procedures for the identified or potential hazards. - Set-up, use, and limitations of all equipment such as emergency equipment, ventilation equipment (blowers), hazardous energy control, isolation and lockout equipment, air quality monitors (e.g., oxygen/combustible meters) and other control equipment that will be used while in the confined space. - Set-up, use, and limitations of all personal protective equipment (e.g., full-body harness, respirators) that the worker will be using while in the confined space. - Communication systems and retrieval systems (set-up and operation). - All safe work procedures for entering the confined space as outlined in the employer's confined space hazard assessment program. - Procedures to follow in the event of a situation developing that could present additional risk to the worker or an emergency. - First aid and CPR. - The specific work to be done while in the confined space. - To work in a manner that will not …

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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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# 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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# 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

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# What are the hazards in a confined space? (cont.) Skylight Area Cramped Space Heat Gas Fumes # Why is working in a confined space more hazardous than working in other workspaces? Many factors need to be evaluated when looking for hazards in a confined space. There is a smaller margin for error. An error in identifying or evaluating potential hazards can have more serious consequences. In some cases, the conditions in a confined space are always extremely hazardous. In other cases, conditions are life threatening under an unusual combination of circumstances. This variability and unpredictability are why the process of hazard and risk identification and assessment is extremely important and must be taken very seriously each and every time one is done. Some examples include: - The entrance or exit of the confined space might not allow the worker to get out easily should there be a flood or collapse of free-flowing solid. - Self-rescue by the worker is more difficult. - Rescue of the victim is more difficult. The interior configuration of the confined space often does not allow easy movement of people or equipment within it. - Natural ventilation alone will often not be sufficient to maintain breathable quality air. The interior configuration of the confined space does not allow easy movement of air within it. - Conditions can change very quickly. - The space outside the confined space can impact the conditions inside the confined space and vice versa. - Work activities may introduce hazards that were not present initially. Confined Space - Introduction CCOHS

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# Why is working in a confined space more hazardous than working in other workspaces? (cont.) ## What should be done when preparing to enter the confined space? (cont.) The results of the tests for these hazards are to be recorded on the Entry Permit along with the equipment or method(s) that were used in performing the tests. Air testing is often ongoing, depending on the nature of the potential hazards and the nature of the work. Conditions can change while workers are inside the confined space and sometimes a hazardous atmosphere is created by the work activities in the confined space. For more information see our OSH Answers document on Confined Space - Atmospheric Testing. ## How are hazards controlled in confined spaces? Hazards and risks associated with a confined space must first be identified through a risk assessment. After this is done, a hazard control program can be put in place. The traditional hazard control methods found in regular worksites, which are implemented based on the hierarchy of controls, can be effective in a confined space. The most effective controls are elimination and substitution, if these are not possible or if there is remaining risk, then engineering controls should be considered. Administrative controls should also be put in place to complement other controls. The last measure to consider is personal protective equipment. However, often because of the nature of the confined space and depending on the hazard, special precautions not normally required in a regular worksite may also need to be taken. Elimination removes the hazard (e.g., finding another way to complete a job without entering a confined space) and substitution replaces a hazard with a safer one (e.g., using cold work methods instead of hot work). An engineering control commonly used in confined spaces is mechanical ventilation. The entry permit system is an example of an administrative control used in confined spaces. Personal protective equipment (such as res…