A national safety discussion
Preventing Unsafe Energization with Lockout/Tagout Procedures
Ensuring that a piece of equipment is de-energized before any cleaning, oiling, adjusting, repair or maintenance work is performed is an essential safety element. Uncontrolled energies (including stored energies) and uncontrolled motion pose a high risk to workers, equipment, and sometimes the work environment. To prevent incidents, employers have an obligation to ensure that an adequate Lockout/Tagout and De-energization program is in place and functioning across their operations.
Inadequate lockout/tagout is the leading workplace safety risk in Ontario’s food manufacturing industry.
The need for lockout/tagout isn’t limited to the food and beverage industry. All manufacturing environments with equipment that could pose an energization safety risk are included. Historically, the types of injuries sustained by workers have included the following:
- Mechanical crushing
- Entanglement in moving machinery parts
- Cuts and lacerations, even amputation
- Electrical injuries such as shock, burns, and even electrocution
The main CSA standards for lockout tagout are:
- CSA Z460 - Control of Hazardous Energy: Lockout and Other Methods
- CSA Z462 - Workplace Electrical Safety
Provincial occupational health and safety regulations include specific provisions for lockout/tagout. In general, employers are responsible for:
- Having written lockout procedures
- Providing lockout devices and tags
- Training workers so that they know lockout/tagout safety procedures
- Auditing lockout/tagout practices and procedures on a regular basis
What is De-energization?
The CCOHS2 defines de-energization as “a process that is used to disconnect and isolate a system from a source of energy to prevent the release of that energy. By de-energizing the system, the risk that the system could inadvertently, accidentally, or unintentionally cause harm to a person through the release of hazardous energy is eliminated.” For safe de-energization, all sources of energy in each piece of equipment or machinery must be identified, and a means to control or release each energy type must be implemented. Ensuring that the energy sources cannot be restored inadvertently is where the concept of locking out comes in.
What is Lockout?
Lockout is the physical component of preventing unsafe energization. According to CCOHS , lockout is the isolation of energy from the system (machine equipment or process) that physically locks the system in a safe mode. Many different lockout devices are available for compliance with lockout regulations. Examples of locking devices include:
- Safety padlocks that require a key to unlock
- Circuit breaker lockout clamps that keep circuit breakers in the off position
- Lockable cables
- Pneumatic and hydraulic valve lockouts for compressed air and other pressurized systems
- Switch lockouts to secure switches in the off position
What is Tagout?
Tagout is visual communication to help prevent unsafe startup and energization of equipment. Tagout procedures will vary for different situations, but generally require attaching a warning tag with a clear message such as “Do not operate” to the circuit breaker or energy isolating device. The tag is meant to supplement physical lockout protection by providing a clear visual warning.
Which Forms of Energy Need to Be Considered?
The forms of energy that need to be considered will vary depending on the design and operation of a particular piece of equipment, machinery or process. Examples include the following:
- Electrical (mains, auxiliary & control voltage, batteries, capacitors)
- Kinetic/mechanical (items that may continue or be able to move even after the controls are locked out)
- Stored (pneumatic/air, hydraulics, spring tension, gravity, capacitor banks)
- Chemical (equipment, machinery and process in which a chemical process is used to create an action or function)
- Thermal/heat (items that radiate heat or that may burn on contact with the body)
- Radiation (non-ionizing radiation such as lasers and UV light sources as well as ionizing radiation such as X-rays)
How do You Implement Lockout/Tagout Procedures?
There are five main phases of a lockout/tagout safety process:
- Preparation – in this phase, all equipment, machinery, and processes that could pose a re-energization safety risk are identified. Lockout/tagout devices and processes are defined for each piece of equipment.
- Awareness and training – in this phase, employees are notified about the safety risks, and trained on proper lockout/tagout procedures.
- Implementation – lockout/tagout devices are installed so that equipment can be isolated from energy sources when it is powered off.
- Enforcement – this phase is critical in order for the lockout/tagout to reduce risk. Employers need to ensure that employees are verifying that equipment is fully de-energized and isolated before doing any maintenance, repair or other work that could be hazardous if the equipment re-energized.
- Review and audit – For a lockout/tagout program to be effective, it must be kept up to date and audited periodically to ensure its effectiveness and the degree of implementation and practice throughout your operations.
Additional information about Lockout/Tagout is available from the Canadian Centre for Occupational Health and Safety.
RESOURCES: https://www.ccohs.ca/oshanswers/hsprograms/lockout.html https://www.csagroup.org/store/product/2427899/