Lockout/Tagout (LOTO) is a safety procedure used in industrial environments to ensure that hazardous machinery is properly shut down and cannot be restarted until maintenance or repair work is completed. This procedure is essential to protect workers from hazardous energy sources, which may include electrical, mechanical, hydraulic, pneumatic, chemical, thermal, and other types of energy.
The origin of Lockout/Tagout (LOTO)
The development of the Lockout/Tagout (LOTO) procedure dates back to the Industrial Revolution, when the use of machines and equipment in industry increased significantly. As a result, there was a need to improve workplace safety, as there were many serious accidents associated with the use of machines. The earliest safety practices were very rudimentary and based mostly on verbal instructions and simple tools such as switches and valves. However, these measures were often insufficient to ensure the safety of workers.
A significant step in the development of safety practices was taken in 1970, when the Occupational Safety and Health Administration (OSHA) was established in the United States. OSHA’s mission was to improve worker safety and health in the workplace. The new organization brought a more systematic approach to safety management and laid the foundation for future safety standards.
In the 1980s, OSHA recognized the need to develop specific rules and standards to control hazardous energy. This need arose from numerous serious accidents caused by unexpected starts of machinery and equipment during maintenance. On the initiative of OSHA, extensive development work was launched, which finally led in 1989 to the publication of the regulation “Control of Hazardous Energy (Lockout/Tagout)” (29 CFR 1910.147).
This act brought with it clear instructions and requirements for the isolation and control of hazardous energy. The introduction of the LOTO standard marked a significant improvement in worker safety, as it ensured that machinery and equipment remained safely switched off during maintenance. The standard required that all energy sources should be isolated and secured by locking (lockout) and marking (tagout) them appropriately. This ensured that the machines could not be accidentally started before the maintenance work had been safely completed.
Today, LOTO is an integral part of workplace safety culture and has significantly reduced the number of accidents and fatalities in industrial settings.
Lockout/Tagout (LOTO) in global use today
LOTO procedures have since become established as part of industry safety practices around the world. OSHA’s initiatives and regulations have also served as a model for other countries that have developed their own similar standards to protect workers from hazardous energy sources.
- International Standards ISO 45001: The international occupational health and safety standard that guides organizations to improve their safety practices also includes recommendations on LOTO procedures
- European Union Directives: In the EU, occupational safety directives require risk assessment and management, which may include LOTO procedures as part of wider safety protocols
Definitions of Lockout and Tagout
Lockout
Lockout involves placing a lock on a device or system to prevent it from being used. This ensures that the device remains inoperable during service or maintenance.
Tagout
Tagout involves placing a tag on a locked device that provides information about the reason for the lockout, the name of the person who set the lockout, and the date. The tags serve as a warning not to restore the power source or start the device.
Lockout/Tagout Procedure
The steps of connecting LOTO
- Preparation: Identify all energy sources and understand their hazards. Inform affected workers to turn off the device.
- Shutdown: Shut down the machine or device.
- Isolation: Cut off energy sources. This may mean flipping circuit breakers, closing valves, or using other methods of cutting off the flow of energy.
- Lock and tag: Place locks and tags on each energy isolation device.
- Releasing Remaining Energy: Ensure that any remaining or stored energy is released or retained. This may include e.g. draining hydraulic lines and/or releasing spring tension.
- Verification: Make sure that the machine or device has been isolated and de-energized. This may mean trying to start the device, checking the meters, or other methods to ensure that there is no active energy.
The steps to remove LOTO
Once the service or maintenance is completed, the LOTO procedure is ready to be canceled.
- Inspection: Make sure the machine or device is in a safe state for re-energization.
- Notification: Notify all affected employees that the LOTO devices will be removed.
- Removing locks and tags: Only the person who set the lock and tag can remove them.
- Energization: Reconnect the energy sources and start the device. Once the service or maintenance is completed, the LOTO procedure is ready to be gently canceled.
- Inspection: Make sure the machine or device is in a safe state for re-energization.
The importance of LOTO procedure
Lockout/Tagout’s primary goal is to protect workers from unexpected start or energization of machinery and equipment, which could lead to serious injury or death. Proper implementation of LOTO procedures is essential to workplace safety and is an integral part of an effective safety program.
Digitization of the LOTO is part of the Gate Apps tools. Gate Apps makes working more efficient and minimizes the risks of manual work in the industry.
