In this article:
- What are lockout/tagout procedures?
- Components of a compliant lockout/tagout procedure
- Who must be trained on lockout/tagout procedures?
- Examples of different types of lockout/tagout procedures
- Graphical lockout/tagout procedures
- Fully electronic lockout/tagout procedures
- Hidden dangers lesser-known risks to be aware of
As with most work-related incidents, lockout/tagout-related accidents and deaths are avoidable. In fact, according to the Occupational Safety and Health Administration (OSHA), the implementation of lockout/tagout standards helps prevent an estimated 120 fatalities and 50,000 injuries every year in the U.S.
A compliant lockout/tagout program includes implementing and practicing five OSHA-mandated components: corporate policy, machine-specific procedures, training, locks and devices, and annual audits.
What are lockout/tagout procedures?
LOTO procedures are a way to help prevent injuries, even fatal ones, related to hazardous energy. Put simply, a lockout/tagout procedure is an instructional document designed to instruct authorized employees on how to lockout a specific machine.
Lockout can be defined as isolating energy sources with a lock providing physical protection, with every lock accompanied by an information tag. Tagout is isolating energy that cannot be physically locked with an information tag to convey who isolated the energy and to warn against re-energization.
Both steps are vital for controlling hazardous energy and can help prevent permanent injuries or death from electrocution or other dangerous sources of energy like compressed air or pressurized steam. It’s also important that a lockout/tagout happens before maintenance begins on any equipment, so it doesn’t pose a danger to anyone working around it.
By using a lockout/tagout procedure, employees can help protect themselves from an unexpected re-energization or release of stored energy. In addition, companies can find greater efficiency and productivity through these procedures.
Components of a compliant lockout/tagout procedure
To verify that employees are using a compliant procedure, companies should include several components. For example, all procedures should include step-by-step directions to ensure that all hazardous energy is turned off and isolated, including electrical sources and mechanical power sources. They should also include details on how to prevent accidental re-energization of lockout devices.
The information required on each procedure, according to OSHA standards, is as follows:
- a statement of the intended use of the procedures
- methods for shutting down the machine and controlling hazardous energy
- steps for the placement and removal of lockout locks, tags, and devices
- ways to verify that the machine has been properly locked out.
Companies can develop these directions by reviewing previous examples from safety professionals or trade groups. Trade associations like the National Safety Council offer training sessions, videos and additional resources for developing these procedures. Companies that plan on training workers or having third parties come in and perform work can have their lockout procedures independently audited.
Who must be trained on lockout/tagout procedures?
Anyone who performs maintenance or service or repair work on a machine with hazardous energy must be trained on how to lockout and tagout. In addition, anyone who supervises employees must also be trained on lockout/tagout procedures.
When it comes to who needs training in your workplace, employers should take into account OSHA 1910.147 section (c)(7). These requirements state that an employer must confirm that each employee who performs machine servicing involving hazardous energy receives initial training before being assigned work duties involving LOTO procedures. They also require the employer to provide a retraining session for all authorized and affected employees whenever there is a change in their job assignments, a change in machines, equipment or process that present a new hazard, or where there is a change in the energy control procedures.
By OSHA standards, an authorized employee is a person who locks or tags out equipment to perform servicing or maintenance. This includes employees who:
- perform energy source isolation
- implement lockout and/or tagout on machines or equipment
- dissipate potential (stored) energy
- verify energy isolation
- implement actions to release LOTO
- test or position machines or equipment.
Examples of different types of lockout/tagout procedures
Different types of lockout/tagout procedures depend on their uses and requirements. The examples of lockout/tagout procedures provided below are used in various industries, including the chemical, refinery, manufacturing and petrochemical, among others.
Graphical lockout/tagout procedures
The current gold standard for lockout/tagout-procedure formats is undoubtedly the picture-based graphical approach. By including high-quality pictures of the equipment, isolation points, control points, and specific shutdown components, authorized employees can quickly and clearly understand how to lock out the equipment. Additionally, including graphical tags with this solution brings the program together to help authorized users process the lockout/tagout procedure steps more quickly, with less likelihood of them isolating the wrong source.
There is an absolute advantage to having graphical lockout procedures available for daily use, and they inherently make conducting annual auditing tasks more easy and efficient.
Fully electronic lockout/tagout procedures
With the advancement of technology, the ability to maintain only electronic copies of procedures has become a real possibility for many companies. Digital versions may be text-based, line drawings, or graphical procedures, and the advantages are many. To fully implement such a program, companies must have tablets readily available for authorized employee use and solutions available for contractors while on-site. Physical three-ring binders can always serve as a backup, and procedures can still be mounted on the equipment to help enhance the program. For any companies who still print the procedures to institute lockouts, the usage of tablets will have an immediate cost saving by cutting down on paper waste and ensuring the procedures are always up to date.
By keeping only electronic digital lockout/tagout procedures, document control becomes much easier. In addition, record-keeping for procedure usage also improves if good software and documentation are used.
Hidden dangers lesser-known risks to be aware of
It is sometimes difficult to look at a machine and determine all energy sources it possesses. Therefore lockout/tagout procedures must contain more information than just the energy sources that can be locked—they must also inform the employee of the energy sources that are non-lockable. Some common non-lockable energy sources include:
- potential energy – magnetic
- potential energy – capacitance
- potential energy – gravity
- potential energy – spring
- hydraulic energy
- thermal energy
- kinetic energy.
These energy sources can easily be overlooked, but all of them pose a hazard to employees that must be addressed. Some of these non-lockable sources, and the methods to control them, are more obvious than others. Simply waiting a few extra minutes before performing a lockout can render many non-lockable energies inert. Energies such as capacitance, kinetic, and thermal energy need time to dissipate.
Others like gravity, spring, and hydraulic energy take more initiative. Lockout technicians must take it upon themselves to lower all suspended parts, reduce or eliminate potential energy in springs, or bleed the pressure from hydraulic lines to create a safe lockout environment.
Keep in mind that some energy, such as magnetic energy, is always going to be present, and you’ll need to choose the safest way to perform the work. If so, it is important to notify the authorized and affected employees, so that any extra personal protective equipment can be acquired. Magnetic energy has the potential to create pinch points, or launch ferrous tools, and it should be acknowledged before a lockout begins.
This story originally appeared in the October 2021 issue of Plant Services. Subscribe to Plant Services here.
This article is part of our monthly Automation Zone column. Read more from our monthly Automation Zone series.