Hierarchy of controls

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# Hierarchy of Controls (cont.) ## What are examples of engineering control methods? (cont.) Engineering controls can be built into the design of a plant, equipment, or process to minimize the hazard. Engineering controls are a very reliable way to control worker exposures as long as the controls are designed, used, and maintained properly. Examples of engineering controls are: Isolation - separating workers from the hazard by distance or the use of barriers - Enclosures - placing the material or process in a closed system (e.g., enclosed machines, booths, etc.) - Guarding and shielding - using guards around moving parts of machinery - Ventilation - using local exhaust or general dilution ventilation to remove or reduce airborne products - Mechanical lifting devices- using mechanical methods to lift or move objects instead of manual lifting - Guardrails - using guardrails to prevent a fall More information on engineering controls includes the following: ## Process Control Process control involves changing the way a job activity or process is done to reduce the risk. Monitoring should be done before and as well as after the change is implemented to make sure the changes did, in fact, control the hazard. Examples of process changes include to: - Use wet methods rather than dry when drilling or grinding. "Wet method" means that water is sprayed over a dusty surface to keep dust levels down or material is mixed with water to prevent dust from being created. - Use steam cleaning instead of solvent degreasing (but be sure to evaluate the potential high-temperature hazard being introduced, such as heat stress). - Float "balls" on open-surface tanks that contain solvents (e.g., degreasing operations) to reduce solvent surface area and lower solvent loss. - Instead of conventional spray painting, try to dip, paint with a brush, or use "airless" spray paint methods. These methods will reduce the amount of paint that is released into the air. - Decrease …

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# Hierarchy of Controls (cont.) Elimination is the process of removing the hazard from the workplace. It is the most effective way to control a risk because the hazard is no longer present. It is the preferred way to control a hazard and should be used whenever possible. Examples of elimination control methods include: - Purchasing equipment that is not noisy - Using a reach pole, where feasible, for window washing to eliminate working from heights - Removing and properly disposing of products that are stored in the workplace and are no longer being used - Avoiding driving during extreme winter weather conditions ## What is substitution? If eliminating a hazard is not possible, substitution is the next control method that should be considered. Substitution is the act of replacing something with another thing in this case, a hazard is replaced with a less hazardous one. The hazards and risks associated with an alternative must be thoroughly assessed to determine if it is an appropriate replacement. Care must be taken to make sure that the new hazard is actually lower, and that one hazard is not being replaced with another that is just as harmful or more harmful. Examples of substitution controls include: - Replacing solvent-based paints with a water-based alternative - Using a larger granule form of a product instead of a fine powder to reduce dust generation - Using electric motors rather than diesel ones to eliminate diesel exhaust emissions Substitution is often used when workers are exposed to hazardous products. Table 1 below provides some examples: Table 1: Sample Chemical Substitutions Hazard and Risk - Hierarchy of Controls CCOHS

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# Process Safety Management (cont.) ## How can a workplace control the hazards? (cont.) Process safety also requires a system in place to continuously monitor the safety of a process and the effectiveness of the controls. This system ensures any deviations from the normal operating parameters and other potential risks are identified and addressed before an incident or failure occurs. It is important that process control deficiencies and unacceptable levels of risk are dealt with immediately. ## Should workers be involved in process safety? From a high level, this framework is similar to identifying, assessing, and controlling other workplace health and safety hazards. Regarding process safety, it is important to include and consult individuals with relevant engineering and technical expertise. This consultation is required to help make sure all risks and hazards associated with a process have been considered. It is also crucial to consult with workers and consider the risks from their perspective. It is important not only to identify hazards for the process but also for workers who operate and maintain the process and other workers who could be impacted. For example, consider the hazards associated with the operation, cleaning, maintenance, deconstruction, and other activities where a worker could suffer an injury or exposure. Appropriate controls must be in place and continuously monitored based on the hazards and risks to protect workers. Fact sheet first published: 2023-12-13 Fact sheet last revised: 2023-12-13 ## Disclaimer Although every effort is made to ensure the accuracy, currency and completeness of the information, CCOHS does not guarantee, warrant, represent or undertake that the information provided is correct, accurate or current. CCOHS is not liable for any loss, claim, or demand arising directly or indirectly from any use or reliance upon the information. Process Safety Management CCOHS

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# APPENDIX C COMPLIANCE GUIDELINES AND RECOMMENDATIONS FOR PROCESS SAFETY MANAGEMENT (NON-MANDATORY) (cont.) ## 11. Managing Change. (cont.) Copies of process changes need to be kept in an accessible location to ensure that design changes are available to operating personnel as well as to PHA team members when a PHA is being done or one is being updated. ## 12. Investigation of Incidents. Incident investigation is the process of identifying the underlying causes of incidents and implementing steps to prevent similar events from occurring. The intent of an incident investigation is for employers to learn from past experiences and thus avoid repeating past mistakes. The incidents for which OSHA expects employers to become aware and to investigate are the types of events which result in or could reasonably have resulted in a catastrophic release. Some of the events are sometimes referred to as "near misses," meaning that a serious consequence did not occur, but could have. Employers need to develop in-house capability to investigate incidents that occur in their facilities. A team needs to be assembled by the employer and trained in the techniques of investigation including how to conduct interviews of witnesses, needed documentation and report writing. A multi-disciplinary team is better able to gather the facts of the event and to analyze them and develop plausible scenarios as to what happened, and why. Team members should be selected on the basis of their training, knowledge and ability to contribute to a team effort to fully investigate the incident. Employees in the process area where the incident occurred should be consulted, interviewed or made a member of the team. Their knowledge of the events form a significant set of facts about the incident which occurred. The report, its findings and recommendations are to be shared with those who can benefit from the information. The cooperation of employees is essential to an effective incident investigation. The f…

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# Enclosure and Isolation (cont.) ## Ventilation (cont.) Because products are exhausted to the outdoors, you should also check with your local environment ministry or municipality for any environmental air regulations or bylaws that may apply in your area. ## What are examples of administrative controls? Administrative controls involve developing procedures to ensure the work is conducted in a way that minimizes the hazard. Examples include developing or changing policies, implementing or improving training and education, and developing or enhancing work practices and procedures. Administrative controls are ranked lower than elimination, substitution, and engineering controls because these methods do not necessarily remove or reduce the hazard from the workplace. For example, administrative controls limit workers' exposures by scheduling shorter work times in contaminant areas or by implementing other "rules". These control measures have many limitations because the hazard itself is not actually removed or reduced. Administrative controls should be used in combination with other control measures where possible. Methods of administrative control include: - Using job-rotation schedules or a work-rest schedule that limits the amount of time an individual worker is exposed to a substance. - Implementing a preventative maintenance program to keep equipment in proper working order - Scheduling maintenance and other high-exposure operations for times when few workers are present (such as evenings and weekends). - Restricting access to a work area. - Restricting the task to only those competent or qualified to perform the work. - Using signs to warn workers of a hazard. More information about types of administrative controls is provided below: ## Work Practices Elements of safe work practices include: - Developing and implementing safe work procedures or standard operating procedures. - Training and education of employees about the operating procedures …

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# Process Safety Management (cont.) ## What is process safety? (cont.) Developing a comprehensive process safety management system (or process safety plan) for your organization requires forming a cross-functional team of managers, supervisors, and workers who are knowledgeable about the operating systems and work activities. External expertise from engineers and professionals may also be required to ensure compliance with health and safety legislation, environmental legislation, and applicable codes. Collaborating and seeking input from other organizations with similar processes is also recommended to make sure all the hazards and risks have been identified and adequate controls are in place. ## How is process safety analyzed? The complexity of a process safety analysis will depend on the type of process. The analysis includes identifying potential hazards and assessing the risks. Multiple methods, frameworks and terminology are used for analyzing and strengthening process safety. Examples include: - Process Hazard Analysis (PHA) - Failure Mode and Effects Analysis (FMEA) - Hazard and Operability Study (HAZAOP) - Fault Tree Analysis (FTA) - Customized Checklists - CSA Standard Z767:17 Process Safety Management When there are changes made to a process, or there are other changes that can impact a process (e.g., climate change), the hazards and risks need to be identified and assessed again, and the control measures revalidated, with the required modifications to the controls being made if needed. ## Identifying potential hazards It is important to identify. the potential sources of harm or failure associated with a process throughout its lifecycle. These include chemical, fire and explosion hazards and natural or climate-related hazards, such as wildfires, flooding, severe winds, high temperatures, and storms. It is also important to consider worst-case situations and scenarios (e.g., extreme weather events) to identify all potential hazards. ## Asses…

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# Process Safety Management (cont.) ## How can a workplace control the hazards? (cont.) - Adequate secondary containment for hazardous chemicals - Proper design of building structures, such as walls and equipment to prevent the spread of a fire and to withstand damage from a fire or explosion. Requirements are often outlined in building codes and fire codes. - Making sure equipment and process components are designed, constructed, installed, and maintained in accordance with the manufacturer's requirements and in accordance with the applicable legislation (e.g., health and safety legislation, building codes, electrical codes, fire codes, pressure vessel codes, etc.) Administrative controls include training and educating workers and developing or improving work policies, practices, and procedures. Examples of work practices and procedures include: - Maintenance planning and work - Developing clear instructions for workers on how to monitor and operate the process safely under all potential conditions - Developing emergency response procedures - Developing business continuity plans Examples of training include: - Making sure workers understand how to safely monitor and operate the process controls - computerized process controls may add complexity to the operations, and workers need to be familiar with all alarms and how to monitor and control the operating parameters. - Training and drills on emergency response procedures Personal Protective Equipment (PPE) is the last line of defence against a hazard and should only be used in addition to other control measures. This control provides protection for the worker. Using this control includes making sure workers responsible for operating and maintaining a process and those who respond to emergencies have access to the required PPE to perform their duties safely. There are many types of PPE, which include respiratory protection, head protection, skin protection, eye and face protection, gloves, protective fo…

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# How is a risk assessment done? In general, to do an assessment, you should: 1. Assemble a risk assessment team. Assessments should be done by a competent person or team of individuals who have a good working knowledge of the situation being studied. Include the supervisors and workers who work with the process under review on the team or as sources of information, as these individuals are the most familiar with the operation. The health and safety committee or representative should also be consulted. 2. Select the job or process to assess. Refer to the above section, "When should a risk assessment be done", to help prioritize your assessments. Ideally, risk assessments should be done for all jobs. Jobs or tasks with higher injury and illness rates, worker concerns, and other factors should be considered first. 3. Break down the job or process into tasks. Divide the job or process into tasks or basic steps to better understand the hazards. 4. Identify the hazards of each task. After the basic steps or tasks have been recorded, identify the hazards of each step or task. List the hazards based on observations and inspections, previous causes of incidents and injuries, feedback from workers and supervisors directly involved in the task, and other considerations. 5. Assess the risk of each hazard. For each hazard, determine the likelihood of harm, such as an injury or illness occurring, and its severity. Use a risk assessment method appropriate for your workplace (see further below for details on risk assessment methods). Consider normal operational situations as well as non-standard events such as maintenance, shutdowns, power outages, emergencies, extreme weather, etc. Review all available health and safety information about the hazard, such as Safety Data Sheet (SDS), manufacturer's literature, information from reputable organizations, results of testing, workplace inspection reports, records of workplace incidents (accidents), including information about the …

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# Process Safety Management (cont.) ## Assessing the risk of the hazards (cont.) Risk assessment takes into account the severity of the consequences (e.g., the potential impact on people, environment, and property) and the probability or likelihood of the consequences occurring. Process safety often requires the use of modelling tools or other techniques for assessing the severity and probability. ## How can a workplace control the hazards? After the hazards have been identified and the risks assessed, appropriate control measures can be implemented, or existing controls can be modified if needed. It is important to have redundancies in place if a control measure fails or is breached. This higher level of protection can be accomplished by adopting a layer of controls. The hierarchy of controls, which is a step-by-step approach to eliminate or reduce the risk of workplace hazards, should be considered. The hierarchy of controls prioritizes controls from the most effective level of protection to the least effective level of protection. Elimination is the most effective method of control because it involves removing the source of the hazard. This control typically involves the removal of a hazardous substance or process. For example, removing a step in a process that is not needed. Substitution is also very effective and involves using an alternative chemical or process that is less hazardous. For example, replacing a highly toxic and flammable chemical used in a process with a safer alternative. Engineering Controls are very important for process safety and involve steps or methods that are built into the design of the plant, equipment, or process to minimize the hazard. They are a reliable way to remove or control workplace hazards as long as the controls are designed, used, and maintained properly. Examples of engineering controls include: - Appropriate ventilation - Pressure or explosion relief venting - Automated process controls for maintaining safe o…